:v4.

ELECTRONICS TECHNICIAN 3 & 2

BUREAU OF NAVAL PERSONNEL

NAVY TRAINING COURSE

NAVPERS 10195

Digitized by the Internet Archive in 2009

http://www.archive.org/details/electronicstechnOOunit

PREFACE

This training course is written for men of the U. S. Navy and Naval Reserve who are interested in qualifying for Electronics Technician Third and Second Class. Combined with the necessary practical experience, this training course will aid you in preparing for the advancement- in- rating examination.

The qualifications for advancement are listed in the Manual of Qualifi- cations for Advancement in Rating, NavPers 18068-B. Because examina- tions for advancement in rating are based on these qualifications, you should refer to them for guidance.

This training course was prepared by the Training Publications Divi- sion, Naval Personnel Program Support Activity, Washington, D. C, for the Bureau of Naval Personnel. Technical assistance was provided by the Electronics Technician School, Naval Training Center, Great Lakes, Illinois; Naval Ship Systems Command; and other activities cognizant of electronic equipments and the duties of Electronics Technicians.

UNITED STATES

GOVERNMENT PRINTING OFFICE

WASHINGTON: 1968

Stock Ordering No. 0500-070-2000

For sale by the Superintendent ot Documents, U.S. Government Printing 0£Bce Washington, D.C. 20402 - Price $3.76

THE UNITED STATES NAVY

GUARDIAN OF OUR COUNTRY

The United States Navy is responsible for maintaining control of the sea and is a ready force on watch at home and overseas, capable of strong action to preserve the peace or of instant offensive action to win in war.

It is upon the maintenance of this control that our country's glorious future depends: the United States Navy exists to make it so.

WE SERVE WITH HONOR

Tradition, valor, and victory are the Navy's heritage from the past. To these may be added dedication, discipline, and vigilance as the watchwords of the present and the future.

At home or on distant stations we serve with pride, confident in the respect of our country, our shipmates, and our families.

Our responsibilities sober us; our adversities strengthen us.

Service to God and Country is our special privilege. We serve with honor.

THE FUTURE OF THE NAVY

The Navy will always employ new weapons, new techniques, and greater power to protect and defend the United States on the sea, under the sea, and in the air.

Now and in the future, control of the sea gives the United States her greatest advantage for the maintenance of peace and for victory in war.

Mobility, surprise, dispersal, and offensive power are the keynotes of the new Navy. The roots of the Navy lie in a strong belief in the future, in continued dedication to our tasks, and in reflection on our heritage from the past.

Never have our opportunities and our responsibilities been greater.

11

CONTENTS

CHAPTER Page

1. Advancement 1

2. Maintenance 9

3. Use of special test equipment 48

4. Radio receivers 105

5. Radio transmitters, Part I 146

6. Radio transmitters, Part II 177

7. Multicouplers and distribution systems 217

8. Teletype and facsimile terminal equipment 256

9. Communications multiplexing 299

10. Electronic aids to navigation. Part I 324

11. Electronic aids to navigation. Part II 378

12. Search radar 411

13. Radar repeaters 444

14. Special purpose equipments 485

15. Satellite navigation 499

APPENDIX

I. Training film list 526

INDEX 538

in

READING LIST

NAVY TRAINING CO JRSES

Basic Electricity, NavPers 10086-A Basic Electronics, NavPers 10087-B Introduction to Electronics, NavPers 10084 Basic Handtools, NavPers 10085-A Blueprint Reading and Sketching, NavPers 10077-B Mathematics Vol, 1, NavPers 10069-C Mathematics Vol. 2, NavPers 10071-A Mathematics Vol. 3, NavPers 10073 Standard First Aid, NavPers 10081-B

OTHER PUBUCATIONS

Naval Ships Technical Manual, Chapter 9670

USAFI TEXTS

United States Armed Forces Institute (USAFI) courses for additional reading and study are available through your Educations Services' Of- ficer.* The following courses are recommended:

A788 Introduction to Electronics I

A789 Introduction to Electronics II

C166 Advanced Algebra

CI 76 Plane Geometry I

CI 77 Plane Geometry n

C188 Trigonometry

♦"Members of the United States Armed Forces Reserve components, when on active duty, are eligible to enroll for USAFI courses, services, and materials if the orders calling them to active duty specify a period of 120 days or more, or if they have been on active duty for a period of 120 days or more, regardless of the time specified on the active duty orders,"

iv

CHAPTER 1

ADVANCEMENT

This training course has been prepared for men of the Navy and of the Naval Reserve, who are studying for advancement to the rates of Electronics Technician 3 and Electronics Tech- nician 2.

The Electronics Technician qualifications used as a guide in the preparation of this train- ing course are those contained in Revision A of the Manual of Qualifications for Advancement in Rating, NavPers 18068.

Chapter 2 of this training course contains information on the Navy 3-M system, records, and reports as they pertain to the Electronics Technician. Chapter 3 discusses the operation and use of the radio interference measuring set, spectrum analyzer, absorption wavemeter and echo box. Chapter 4 covers radio receiving sets AN/SRR-11, 12, and 13, AN/WRR-2, and AN/ WRR-35.A. This chapter also includes a brief discussion of SSB converter CU-591A/URR.

Chapters 5 and 6 describe radio transmitters with special circuits of the AN/SRT-14, 15, and 16, such as antenna tuning and keying circuits being discussed, A brief discussion of shore- based transmitters is contained in chapter 6. Chapter 7 discusses various multicouplers used by the fleet; the types of switching systems used for the transfer of equipment control, an- tenna selections, and radar information distribu- tion.

Chapter 8 presents teletype terminal equip- ment and facsimile equipment used throughout the Navy. The basic principles of communica- tions multiplexing are presented in chapter 9 along with a discussion of telegraph terminal set AN/UCC-1(V). Electronic Aids to Naviga- tion are presented in chapter 10 and 11, using the TACAN system AN/SRN-6, radio direction finder equipment AN/URD-4, and LORAN re- ceiving set AN/UPN-12 as representative equip- ments. Radar is covered in chapter 12 and radar repeaters are discussed in chapter 13, Special

purpose equipment, such as electronic counter- measures, inertial navigation, and satellite communication equipment is presented in chap- ter 14. Chapter 15 is devoted entirely to Satel- lite Navigation which covers the overall Navy Satellite Navigation System and the AN/SRN- 9 as the representative equipment.

The remainder of this chapter gives informa- tion on the enlisted rating structure, the Elec- tronics Technician rating, requirements and procedures for advancement in rating, and refer- ences that will help you in working lor advance- ment and in performing your duties as an Elec- tronics Technician. Therefore, it is strongly recommended that you study this chapter care- fully before beginning intensive study of the re- mainder of this training course.

Throughout this training course, the term "cycle," or "cycles per second," or the abbre- viation CPS is used to express electrical fre- quency in cycles per second. Recently, in effecting world-wide standardization of various units of measurement, the term "Hertz" ab- breviated H^) has been adopted to express cycles per second and will be used in later revisions of this training course.

THE ENLISTED RATING STRUCTURE

The two main types of ratings in the present enlisted rating structure, are general ratings and service ratings.

GENERAL RATINGS identify broad occupa- tional fields of related duties and functions. Some general ratings include service ratings; others do not. Both Regular Navy and Naval Re- serve personnel may hold general ratings.

SERVICE RATINGS identify subdivisions or specialties within a general rating. Although service ratings can exist at any petty officer level, they are most common at the P03 and P02 levels. Both Regular Navy and Naval Re- serve personnel may hold service ratings.

ELECTRONICS TECHNICIAN 3 & 2

THE ELECTRONICS TECHNICL^N RATING

Electronics Technicians maintain, repair, calibrate, tune, and adjust electronic devices and equipment. Electronics Technician ratings are included in the personnel allowance for practi- cally all Navy ships including repair ships and tenders. The rating was established in 1948, and includes service ratings ETR (radar) and ETN (communications) at petty officer 3 & 2 levels. For advancement to ETl, the candidate must be qualified in both service ratings. Enlisted classification codes for the rating are listed in the Manual of Navy Enlisted Classifications, NavPers 15105 (revised). Classification codes identify men with special training and/or quali- fications on equipments such as special radars, AEW systems, automatic landing systems, com- munications security devices equipment, inertial navigation equipment, ground controlled ap- proach systems, TACAN systems and electronic standards equipment.

ADVANCEMENT IN RATING

Some of the rewards of advancement in rat- ing are easy to see. You get more pay. Your job assignments become more interesting and more challenging. You are regarded with greater respect by officers and enlisted personnel. You enjoy the satisfaction of getting ahead in your chosen Navy career.

But the advantages of advancing in rating are not yoiurs alone. The Navy also profits. Highly trained personnel are essential to the function- ing of the Navy. By each advancement in rating, you increase your value to the Navy in two ways. First, you become more valuable as a specialist in your own rating. And second, you become more valuable as a person who can train others and thus make far-reaching contributions to the entire Navy.

HOW TO QUALIFY FOR ADVANCEMENT

What must you do to qualify for advancement in rating? The requirements may change from time to time, but usually you must:

1. Have a certain amount of time in your present grade.

2. Complete the required military and oc- cupational training courses.

3. Demonstrate your ability to perform all the PRACTICAL requirements for advancement by completing the Record of Practical Factors,

NavPers 1414/1. In some cases the Record of Practical Factors may contain the old form num- ber, NavPers 760.

4. Be recommended by your commanding officer, after the petty officers and officers supervising your work have indicated that they consider you capable of performing the duties of the next higher rate.

5. Demonstrate your KNOWLEDGE by pass- ing a written examination on (a) military require- ments and (b) occupational qualifications.

Some of these general requirements may be modified in certain ways. Figure 1-1 gives a more detailed view of the requirements for ad- vancement of active duty personnel; figure 1-2 gives this information for inactive duty person- nel.

Remember that the requirements for ad- vancement can change. Check with your division officer or training officer to be sure that you know the most recent requirements.

Advancement in rating is not automatic. After you have met all the requirements, you are ELIGIBLE for advancement. You will actually be advanced in rating only if you meet all the requirements (including making a high enough score on the written examination) and if the quotas for your rating permit your advancement.

HOW TO PREPARE FOR ADVANCEMENT

What must you do to prepare for advance- ment in rating? You must study the qualifica- tions for advancement, work on the practical factors, study the required Navy Training Courses, and study other material that is re- quired for advancement in your rating. To pre- pare for advancement, you will need to be familiar with (1) the Quals Manual, (2) the Record of Practical Factors, NavPers 1414/1, (3) a Nav- Pers publication called Training Publications for Advancement in Rating, NavPers 10052, and (4) applicable Navy Training Courses. The following sections describe them and give you some prac- tical suggestions on how to use them in prepar- ing for advancement.

The Quals Manual

The Manual of Qualifications for Advance- ment in Rating, NavPers 18068 B (with changes), gives the minimum requirements for advance- ment to each rate within each rating. This manual is usually called the "Quals Manual," and the qualifications themselves are often called

Chapter 1-ADVANCEMENT

ACTIVE DUTY ADVANCEMENT REQUIREMENTS

REQUIREMENTS *	El to E2	E2 to E3	#tE3 to E4	#E4 toES	tE5 toE6	tE6toE7	t E7 to E8	t E8 to E9
SERVICE	4 mos. service— or comple- tion of recruit training.	6 mos. as E-2.	6 mos. as E-3.	12 mos. as E-4.	24 mos. as E-5.	36 mos. as E-6. 8 years total enlisted service.	36 mos. OS E-7. 8 of 11 years total service must be enlisted.	24 mos. as E-8. 10ofl3 years total service must be enlisted.
SCHOOL	Recruit Training.		Class A for PR3, DT3, PT3. AME3, HM3			Class B for AGC MUC, MNC.
PRACTICAL FACTORS	Locally prepared check- offs.	.Records of Practical Factors, NavPers 1414/1, must be completed for E-3 and all PO advancements.
PERFORMANCE TEST		Specified ratings must complete applicable performance tests be- fore taking examinations.
ENLISTED PERFORMANCE EVALUATION	As used by CO when approving advancement.	Counts toward performance factor credit in ad- vancement multiple.
EXAMINATIONS**	locally prepare( tests.	See below.	Navy-wide examinations required for all PO advancements.	Navy-wide, selection board.
NAVY TRAINING COURSE (INCLUD- ING MILITARY REQUIREMENTS)		Required for E-3 and all PO advancements unless waived because of school comple- tion, but need not be repeated if identical course has already been completed. See NavPers 10052 (current edition).	Correspondence courses and recommended reading. See NavPers 10052 (current edition).
AUTHORIZATION	Commanding OfTicer	U.S. Naval Examining Center	Bureau of Naval Personnel

* All advancements require commanding officer's recommendation .

t 1 year obligated service required for E-5 and E-6; 2 years for E-6, E-7, E-8 and E-9. # Military leadership exam required for E-4 and E-5. *♦ For E-2 to E-3, NAVEXAMCEN exams or locally prepared tests may be used.

Figure 1-1.— Active duty advancement requirements.

3

ELECTRONICS TECHNICIAN 3 & 2

INACTIVE DUTY ADVANCEMENT REQUIREMENTS

REQUIREMENTS *	El to E2	E2toE3	E3 to E4	E4toE5	E5 to E6	E6toE7	E8	E9
TOTAL TIME IN GRADE	4 mos.	6 mos.	1 5 mos.	18 mos.	24 mos.	36 mos.	36 mos.	24 mos.
TOTAL TRAINING DUTY IN GRADE t	14 days	14 days	14 days	14 days	28 days '	12 days	42 days	28 days
PERFORMANCE TESTS		— ■ ■ i 1 Specified ratings must complete opplicoble performance tests before taking exami- nation.
DRILL PARTICIPATION	Satisfactory participation as a member of a drill unit.
PRACTICAL FAQORS (INCLUDING MILITARY REQUIREMENTS)	Record of Practical Factors, NavPers 1414/1, must be completed for all advancements.
NAVY TRAINING COURSE (INCLUDING MILITARY REQUIRE- MENTS)	Completion of applicable course or courses must be entered In service record.
EXAMINATION	Standard Exam	Standard Exam or Rating Training.	Standard Exam required for all PO Advancements.	Standard Exam, Selection Board. Also pass Mil. Leadership Exam for E-4 and E-S.
AUTHORIZATION	Commanding Officer	U.S. Naval Examining Center	Bureau of Naval Personnel

* Recommendation by commanding officer required for all advancements, t Active duty periods may be substituted for training duty.

Figure 1-2.— Inactive duty advancement requirements.

4

Chapter 1-ADVANCEMENT

"quals." The qualifications are of two general types: (1) military requirements, and (2) oc- ! cupational qualifications.

MILITARY REQUIREMENTS apply to all rat- ings rather than to any one particular rating. Military requirements for advancement to third class and second class petty officer rates deal with military conduct, naval organization, mili- tary justice, security, watch standing, and other subjects which are required of petty officers in all ratings.

OCCUPATIONAL QUALIFICATIONS are re- quirements that are directly related to the work of each rating.

Both the military requirements and the occu- pational qualifications are divided into subject matter groups; then, within each subject matter group, they are divided into PRACTICAL FAC- TORS and KNOWLEDGE FACTORS. Practical factors are things you must be able to DO. Knowledge factors are things you must KNOW in order to perform the duties of your rating.

In most subject matter areas, you will find both practical factor and knowledge factor quali- fications. In some subject matter areas, you may find only practical factors or knowledge factors. It is important to remember that there are some knowledge aspects to all practical fac- tors, and some practical aspects to most knowl- edge factors. Therefore, even if the Quals Man- ual indicates that there are no knowledge factors for a given subject matter area, you may still expect to find examination questions dealing with the knowledge aspects of the practical factors listed in that subject matter area.

In summary, then, the written examination for advancement in rating may contain questions relating to the practical factors and to the knowl- edge factors of both the military requirements and the professional qualifications. If you are working for advancement to second class, re- member that you may be examined on third class qualifications as well as on second class qualifi- cations.

You are required to pass a Navy- wide mili- tary/leadership examination for E-4 or E-5, as appropriate, before participating in the occupa- tional examinations. The military/leadership examinations for both levels are given quarterly. Candidates are required to pass the applicable military/leadership examination only once. Each of these examinations consists of 100 ques- tions based on information contained in the Manual of Qualifications for Advancement in Rat-

ing, NavPers 18068-B and Training Publications for Advancement in Rating, NavPers 10052. ~ The Navy- wide occupational examination for pay grades E-4 and E-5 will contain 150 ques- tions related to occupational areas of your rating.

The Quals Manual is kept current by means of changes. The occupational qualifications for your rating which are covered in this training course were current at the time the course was printed. By the time you are studying this course, however, the quals for your rating may have been changed. Never trust any set of quals until you have checked it against a n UP- TO- DATE copy in the Quals Manual.

Record of Practical Factors.

Before you can take the servicewide examina- tion for advancement in rating, there must be an entry in your service record to show that you have qualified in the practical factors of both the military requirements and the occupational qualifications. A special form known as the RECORD OF PRACTICAL FACTORS, NavPers 1414/1 is used to keep a record of your practical factor qualifications. This form is available for each rating. The form lists all practical factors, both military and occupational. As you demon- strate your ability to perform each practical factor, appropriate entries are made in the DATE and INITIALS columns.

Changes are made periodically to the Manual of Qualifications for Advancement in Rating, and revised forms of NavPers 1414/1 are provided when necessary. Extra space is allowed on the Record of Practical Factors for entering addi- tional practical factors as they are published in changes to the Quals Manual. The Record of Practical Factors also provides space for re- cording demonstrated proficiency in skills which are within the general scope of the rating but which are not identified as minimum qualifica- tions for advancement.

If you are transferred before you qualify in all practical factors, the NavPers 1414/1 form should be forwarded with your service record to your next duty station. You can save yourself a lot of trouble by making sure that this form is actually inserted in your service record before you are transferred. If the form is not in your service record, you may be required to start all over again and requalify in the practical fac- tors which have already been checked off.

ELECTRONICS TECHNICIAN 3 & 2

NavPers 10052

Training Publications for Advancement in Rating. NavPers 10052 (revised), is a veryim- portant publication for anyone preparing for ad- vancement in rating. This bibliography lists required and recommended Navy Training Courses and other reference material to be used by personnel working for advancement in rating. NavPers 10052 is revised and issued once each year by the Bureau of Naval Personnel. Each revised edition is identified by a letter following the NavPers number. When using this publica- tion, be SURE that you have the most recent edition.

If extensive changes in qualifications occur in any rating between the annual revisions of NavPers 10052, a supplementary list of study material may be issued in the form of a BuPers Notice. When you are preparing for advance- ment, check to see whether changes have been made in the qualifications for your rating. If changes have been made, see if a BuPers Notice has been issued to supplement NavPers 10052 for your rating.

The required and recommended references are listed by rate level in NavPers 10052. If you are working for advancement to third class, study the material that is listed for third class. If you are working for advancement to second class, study the material that is listed for second class; but remember that you are also respon- sible for the references listed at the third class level.

In using NavPers 10052, you will notice that some Navy Training Courses are marked with an asterisk (*). Any course marked in this way is MANDATORY— that is, it must be completed at the indicated rate level before you can be eligible to take the servicewide examination for advancement in rating. Each mandatory course may be completed by (1) passing the appropriate enlisted correspondence course that is based on the mandatory training course; (2) passing locally prepared tests based on the informa- tion given in the training course; or (3) successfully completing an appropriate Class A course.

Do not overlook the sectionof NavPers 10052 which lists the required and recommended refer- ences relating to the military requirements for advancement. Personnel of ALL ratings must complete the mandatory military requirements training course for the appropriate rate level be- fore they can be eligible to advance in rating.

The references in NavPers 10052 which are recommended but not mandatory should also be studied carefully. ALL references listed in Nav- Pers 10052 may be used as source material for the written examinations, atthe appropriate rate levels.

Navy Training Courses

There are two general types of Navy Train- ing Courses. RATING COURSES (such as this one) are prepared for most enlisted ratings. A rating training course gives information that is directly related to the occupational qualifications of ONE rating. SUBJECT MATTER COURSES or BASIC COURSES give information that ap- plies to more than one rating.

Navy Training Courses are revised from time to time to keep them up to date technically. The revision of a Navy Training Course is identified by a letter following the NavPers number. You can tell whether any particular copy of a Navy Training Course is the latest edition by check- ing the NavPers number and the letter following this number in the most recent edition of List of Training Manuals and Correspondence Courses. NavPers 10061. (NavPers 10061 is actually a catalog that lists all current training courses and correspondence courses; you will find this catalog useful in planning your study program.)

Navy Training Courses are designed to help you prepare for advancement in rating. The fol- lowing suggestions may help you to make the best use of this course and other Navy training publi- cations when you are preparing for advancement in rating.

1. Study the military requirements and the occupational qualifications for your rating before you study the training course, and refer to the quals frequently as you study. Remember, you are studying the training course primarily in order to meet these quals.

2. Set up a regular study plan. It will probably be easier for you to stick to a schedule if you can plan to study at the same time each day. If possible, schedule your studying for a time of day when you will not have too many in- terruptions or distractions.

3. Before you begin to study any part of the training course intensively, become familiar with the entire book. Read the preface and the table of contents. Check through the index. Look at the appendixes. Thumb through the book with- out any particular plan, looking at the

Chapter 1- ADVANCEMENT

illustrations and reading bits here and there as you see things that interest you.

4. Look at the training course in more de- tail, to see how it is organized. Look at the table of contents again. Then, chapter by chapter, read the introduction, the headings, and the sub- headings. This will give you a pretty clear pic- ture of the scope and content of the book. As you look through the book in this way, ask yourself some questions: What do 1 need to learn about this? What do I already know about this? How is this information related to information given in other chapters? How is this information re- lated to the qualifications for advancement in rating?

5. When you have a general idea of what is in the training course and how it is organized, fill in the details by intensive study. In each study period, try to cover a complete unit— it may be a chapter, a section of a chapter, or a subsection. The amount of material that you can cover at one time will vary. If you know the sub- ject well, or if the material is easy, you can cover quite a lot at one time. Difficult or un- familiar material will require more study time.

6. In studying any one unit— chapter, sec- tion, or subsection— write down the questions that occur to you. Many people find it helpful to make a written outline of the unit as they study, or at least to write down the most important ideas.

7. As you study, relate the information in the training course to the knowledge you already have. When you read about a process, a skill, or a situation, try to see how this information ties in with your own past experience.

8. When you have finished studying a unit, take time out to see what you have learned. Look back over your notes and questions. Maybe some of your questions have been answered, but per- haps you still have some that are not answered. Without looking at the training course, write down the main ideas that you have gotten from study- ing this unit. Don't just quote the book. K you can't give these ideas in your own words, the chances are that you have not really mastered the information.

9. Use Enlisted Correspondence Courses whenever you can. The correspondence courses are based on Navy Training Courses or on other appropriate texts. As mentioned before, com- pletion of a mandatory Navy Training Course can be accomplished by passing an Enlisted Corres- pondence Course based on the Navy Training Course. You will probably find it helpful to take

other correspondence courses, as well as those based on mandatory training courses. Taking a correspondence course helps you to master the information given in the training course, and also helps you see how much you have learned. 10. Think of your future as you study Navy Training Courses. You are working for advance- ment to third class or second class right now, but someday you will be working toward higher rates. Anything extra that you can learn now will help you both now and later.

SOURCES OF INFORMATION

Besides training courses, NavPers 10052 lists official publications on which you may be examined. You should not only study the sections required, but should become as familiar as pos- sible with all publications you use.

One of the most useful things you can learn about a subject is how to find out more about it. No single publication can give you all the infor- mation you need to perform the duties of your rating. You should learn where to look for ac- curate, authoritative, up-to-date information on all subjects related to the military requirements for advancement and the occupational qualifica- tions of your rating.

PUBLICATIONS YOU SHOULD KNOW

Electronic technical publications i n c 1 u d e various handbooks, bulletins, and manuals pub- lished and distributed by the Ship Systems Com- mand, and manufacturers' technical manuals. The Requisitioning Guide and Index of Forms and Publications, NavSandA 2002, furnishes a complete list of NavShips technical publications along with instruction for ordering copies.

One bulletin of great importance to the ET is Electronics Information Bulletin (EIB;, NavShips 0967-00l-3(---), published bi-weekly for naval electronics activities. A complete file of these bulletins should be maintained.

This bulletin lists field changes and correc- tions that must be made in instruction books and other publications that are used in the mainte- nance of electronic equipment. It also lists elec- tronics publications that become available, and gives valuable suggestions, from case histories, for servicing electronic equipment.

The recently revised Electronics Installation and Maintenance Book (EIMB) furnishes data applying to all types of electronics equipment including the theory of operation of basic

ELECTRONICS TECHNICIAN 3 & 2

electronic circuits. The EIMB is organized and issued as 12 separate handbooks, each with its own NavShips number. A complete listing of all handbooks, stock numbers, and most recent changes can be found in current issues of the EIB.

Another NavShips publication of importance to the ET is the Naval Ships Technical Manual, NavShips 250-000^ This manual is the basic doctrine publication of the Naval Ship Systems Command. Chapter 9670 (formerly chap. 67) is of particular importance to the ET and should be a part of the ET library.

The Naval Ship Systems Command Technical News is a monthly publication which contains interesting and useful articles on all aspects of shipboard engineering. This magazine is par- ticularly useful because it presents information which supplements and clarifies information contained in the Naval Ships Technical Manual and because it presents information on new de- velopments.

The manufacturers' technical manuals that are furnished with most electronic equipment are valuable sources of information on opera- tion, maintenance and repair. The manu- facturers' technical manuals that deal with Naval Ship Systems Command equipment are usually given NavShips numbers.

Some publications are subject to change or revision from time to time— some at regular intervals, others as the need arises. When using

any publication that is subject to change or re- vision, be sure that you have the latest edition. When using any publication that is kept current by means of changes, be sure you have a copy in which all official changes have been made. Studying canceled or obsolete information will not help you to do your work or to advance in rating; it is likely to be a waste of time and may even be seriously misleading.

TRAINING FILMS

Training films available to naval personnel are a valuable source of supplementary informa- tion on many technical subjects. A selected list of training films that may be useful to you is given in Appendix I of this training course. Other films that may be of interest are listed in the United States Navy Film Catalog. NavWeps 10-1- 777. This catalog, published in 1966, supersedes three earlier publications: the former catalog with the same title but numbered NP 10000- A; the Supplement, NavWeps 10-1772; and the Navy Classified Film Catalog, NavPers 10001-A.

As you know, procedures sometimes change rapidly. Thus some film become obsolete rapidly. If a film is obsolete only in part, it may still have sections that are useful, but it is im- portant to note procedures that have changed. If there is any doubt, verify current procedures by looking them up in EIMB, EIB, Naval Ships Technical Manual, or other applicable sources.

CHAPTER 2

MAINTENANCE

Maintenance, as defined by the Naval Ships rechnical Manual, is the function of retaining naterial in, or restoring it to, a serviceable jondition. Its phases include servicing, repair, nodification, modernization, overhaul, and test- PREVENTIVE MAINTENANCE

' Preventive or scheduled maintenance is de- ined as those measures taken periodically to ichieve maximum efficiency in performance, 0 ensure continuity of service, to reduce major )reakdowns, and to lengthen the useful life of he equipment or system. This form of main- enance consists principally of cleaning, lubri- lation, and periodic tests aimed at discovering londitions whi^.h, if not corrected may lead to nalfunctions.

To realize optimum results from the regular unctional tests, a careful record of the per- ormance data on each equipment must be kept. The value of these records may be demon- itrated in a number of ways. Comparison of lata taken on a particular equipment at dif- erent times may reveal slow, progressive Irifts that may be too small to show up sig- lificantly in any one test. While the week-to- ^eek changes may be slight, they should be oUowed carefully so that necessary replace- aents or repairs may be effected before the aargin of performance limits is reached. Any narked variations should be regarded as ab- ormal, and should be Investigated immediately, mother advantage in keeping systematic rec- ords of performance and servicing data is that aaintenance personnel develop a more rapid amiliarization with the equipment involved. ?he accumulated experience contained in the •ecords serves as a guide to swift and accu- ■ate troubleshooting.

THE 3-M SYSTEM

The Navy Maintenance and Material Manage- ment {3-M) System has been implemented in the Navy as an answer to the ever-present problem of maintaining a high degree of material readi- ness. Although the (3-M) System is designed to improve the degree of readiness, its effective- ness and reliability are dependent upon you, the individual. The accuracy with whichyou perform your work, along with the neat and complete recording of required data on the prescribed forms, is one of the keys to the degree of readi- ness of your ship and therefore is a reflection of your success as a petty officer.

The two basic elements of the 3-M System are the Planned Maintenance System (PMS) and the Maintenance Data Collection System (MDCS). The Planned Maintenance System provides a uniform system of planned preventive mainte- nance. The Maintenance Data Collection Sys- tem provides a means of collecting necessary maintenance and supply data, in a form suitable for rapid machine processing. A Man-hour Accounting System is used aboard repair ships and tenders in conjunction with the Maintenance Data Collection System.

Preventive maintenance should not be con- fused with corrective maintenance. Preventive maintenance is a scheduled check on select parts of a piece of equipment. Corrective maintenance is the repair of equipment.

As a third or second class ET, you will be concerned with both the Planned Maintenance System (PMS) and certain portions of the Maintenance Data Collection System (MDCS) as discussed in this chapter.

THE PLANNED MAINTENANCE SYSTEM

Planned maintenance reduces casualties and saves the cost of major repairs. The PMS is

ELECTRONICS TECHNICIAN 3 & 2

designed to define the minimum planned mainte- nance required, to schedule and control per- formance, to describe the methods and tools to be used, and to aid in the prevention and detection of impending casualties.

In establishing minimum planned mainte- nance requirements for each piece of equip- ment, the Naval Ships Technical Manual, manu- facturers' technical manuals, and applicable drawings are critically reviewed. If the planned maintenance requirements are found to be un- realistic or unclear, they are modified or com- pletely revised before being incorporated into the PMa

It is possible that the planned maintenance prescribed in the PMS may conflict with that prescribed in other documents such as the Naval Ships Technical Manual. Should this happen, it must be remembered that the PMS supersedes and takes precedence over exist- ing requirements set forth in various technical publications inso/far as preventive maintenance is concerned.

The Planned Maintenance System Manual

A master Planned Maintenance System Man- ual is tailored to each department of a specific ship. It contains the minimum planned main- tenance requirements for each maintainable component installed in that particular depart- ment. The department Master Manuals are normally kept in the department offices and are primarily used by the department heads in planning and scheduling the maintenance requirements in their departments.

The departmental Master Manual contains a section for each division or maintenance group within the department. Each divisional section contains a table of contents and a Maintenance Index Page (MIP) for each sys- tem, subsystem, or component involved.

Applicable portions of the PMS Manual (referred to as Space Manuals) are kept in the working space for the equipment involved and serve as a ready reference to the planned maintenance required. Each MIP contains a brief description of the maintenance require- ments and the frequency with which mainte- nance is to be effected. The frequency code is: D— daily, W— weekly, M— monthly, Q— quar- terly, S— semiannually, A— annually, C— over- haul cycle, and R— situation requirement. The frequency codes for the daily, weekly, monthly,

quarterly, semiannual, and annual planned main- tenance actions are self-explanatory. Certain planned maintenance actions are performed once each operational cycle between shipyard over- hauls, during a specified quarter of the cycle, and are designated by the code C. The code R is used to identify those planned maintenance actions which are to be performed prior to getting underway, after a specified number of hours of operation, or to meet other require- ments that only arise during a specific situa- tion (prior to overhaul, for example).

Figure 2-1 shows a Maintenance Index Page (MIP) taken from a typical PMS Manual. In- formation to be found on the MIP includes the system or component involved, a short descrip- tion of each maintenance requirement, the main- tenance frequency code plus a consecutive num- ber starting with "1" for each frequency code assigned, the rate or rates recommended to perform the maintenance, the average time re- quired to perform the maintenance, and related maintenance requirements. The related main- tenance listed is additional planned maintenance which can be completed prior to, in conjunction with, or immediately after the scheduled main- tenance.

Because shipboard application of the PMS will vary slightly from one ship to another, the information found on the MIPs regarding rates recommended to perform the maintenance and the average time required for the task re- quires certain clarification. The maintenance taska are actually performed by personnel available and capable, regardless of what rate is listed on the MIP. The average time re- quired, as listed on the MIP, does not take into account the time required to assemble the necessary tools and materials nor the time required to clean the area and put away the tools at the end of the task.

SCHEDULING OF PLANNED MAINTE- NANCE.—For each division or maintenance group, a cycle schedule which provides a visual display of the planned maintenance requirements (based on the operational cycle of the ship between shipyard overhauls) is displayed in the departmental office. The information to be found on the cycle schedule (fig. 2-2), for any particular division or maintenance group in- cludes the MIP number (column 1) from the PMS Manual, a listing of all the equipment within that particular group for which planned maintenance is required, and the specific quarter

10

Chapter 2 -MAINTENANCE

Sy*l«fn, S«b«y»»«ni, or Component

AN/USM-105A, 105V Oscilloscope

290ATG2 290ATG2 290AIG2

CT 290ATG2 CT 290ATG2

BA38 BA39 BA40

3A41 BA42

R«f*f«nc« Publication*

NAVSHIPS 93658(A)

Mointanonc* K*qwir«in«n«

1. Clean air filter.

1. Verify speed of blower motor.

1. Clean and inspect.

2. Lubricate the blower motor.

1. Test operation.

1. Inventory accessories.

2. Test operation.

3. Deliver oscilloscope to calibration

activity.

ML

These maintenance cards were prepared for this equipment in which the following field changes have been accomplished: 1

Of these, the following field changes affect the maintenance actions: none

New maintenance requirement cards and maintenance index pages will be made available as future field changes are accomplished that affect the prescribed planned maintenance.

W-1 M-1 Q-1

Q-2 S-1

lot*

ETSN ETSN ETSN

ET3 ETSN

Mot

0.1 0.1 0.4

0.4 0.2

None Rone Q-2

Hone Q-2

HAINTCNANCE WDtX PAKE •*«*V FORM 470C-3 « (>4>

BUREAU PASE CONTML NUMBER 1-3/ 2-85

96.171

Figure 2-1.— Maintenance Index Page. 11

ELECTRONICS TECHNICIAN 3 & 2

EQUIP PAGE (1)	a«ss	SCHEDULE AS INDICATED	EACH QUARTER
QUARTER AFTER OVERHAUL
MAINTENANCE GROUP COMMUNICATIONS	: 5 9	2 6 10	3 7 1 1	4 e 12
COMPONENT
C-1	AN/URR-35A					M-1
C-2	TED					M-1
C-3	AM/1365-URT					M-1
C-11	AN/rfRR-2		S-1		S-1	M-1. Q-1
C-1 2	MAT-1	S-1		S-1
_A^	_ ^X^_^	^"S—	— ^		^^^v^^	^^^

CYCLE SCHEDULE OPttiV FCRM 11700-* (»-64)oi07-766-4000

Figure 2-2,— Cycle schedule.

98.172

in which the semiannual, annual, and over- haul cycle planned maintenance actions are to be performed. The cycle schedule also lists the quarterly and the situation require- ment planned maintenance actions which must be scheduled, as well as the monthly planned maintenance requirements.

The cycle schedule is used by the depart- ment head, in conjunction with his division officers and leading petty officers, to make out the quarterly planned maintenance sched- ule. The quarterly schedule (fig. 2-3) dis- played adjacent to the cycle schedule in a holder known as the maintenance control board, gives a visual display of the ship's deploy- ment schedule and the planned maintenance to be performed during that particular quar- ter.

The quarterly schedule has thirteen columns, one for each week in the quarter, for the sched- uling of maintenance throughout the 3- month period.

At the end of each week, the leading petty officer of the division or maintenance group; will update the quarterly schedule by crossing] out (with an X) the preventive maintenance per formed. If a planned maintenance action is not ' completed during the week it is scheduled, the leading petty officer will circle the action on the quarterly schedule. The uncompleted main- tenance is then rescheduled (as shown in figure 2-3) for another week within the same qiiarter, normally as soon as the operating schediile of the ship will allow.

At the close of each quarter, the quarterly schedule is removed from its holder and re- tained on board as a record of the planned

12

Chapter 2 -MAINTENANCE

-^

-T F

r

.

— — r

QUmTERLY »

AINTEHtHCE

SCHEDULE

OPHAV FWM »7(

W-S (»-6U)

==

=—

==

=—

:==:=■

98.173

Figure 2- 3. -Quarterly maintenance schedule.

maintenance completed. This record may be discarded at the beginning of the second quar- ter after the next shipyard overhaul.

The quarterly schedule is also used by your leading petty officer to make out a weekly planned maintenance schedule which is posted in the space where you work. The weekly schedule of planned maintenance should not be considered as the total work for the week. This schedule only covers the scheduled plan- ned maintenance and is in addition to the other routine work, upkeep, and corrective mainte- nance to be done.

The weekly schedule provides a list of the components in the working area, the appropriate page number of the PMS Manual, and spaces for the leading petty officer to use in the

assignment of planned maintenance tasks to specified personnel. The daily and weekly planned maintenance actions are preprmted on the forms and the other maintenance actions are written in by the leading petty officer as required. When the leading petty officer is assured that a maintenance task has been com- pleted he crosses out the maintenance require- ment number on the weekly schedule. If for some reason a task cannot be completed on the day scheduled, the leading petty officer wUl circle the maintenance requirement number and reschedule it for another day. The status of scheduled maintenance is readily available by looking at the weekly schedule.

A sample weekly schedule is shown in figure 2-4. In addition to the weekly

13

ELECTRONICS TECHNICTAN 3 & 2

WORK SCHEDULE FOR WEEK OF

^OQU ST f^-CO

MAtNTENANCE RESPONSIBILITY

M (I-t MKSS

Cff/DER,RD2

WILLIAMS, Et;

DWVER,Erj

BiuMBAcH,SA

->M,

SAMPLE WEEKLY- WORK SCHEDLLE

FORMAT INCLUDES ALL DAILY & WEEKLY CHECKS PREPRINTED

WHERE USED: Posted in Maintenance Group .ork Space in aluminum holder.

OUTSTANDING REPAIRS AND Pm CHECKS DUE IN NEXT < WEEKS

«'H0 USES: Maintenance Group Supervisors and maintenance personnel.

Figure 2-4. -Weekly work schedule.

98.175

maintenance actions, the leading petty officer has assigned Williams the responsibility of re- quirements M-1, M-2, and M-3 on Tuesday and Dwyer the responsibility of S-1 on Wed- nesday. In the far right-hand column, it is noted that maintenance requirement A-1 is listed under outstanding repairs (due within the next 4 weeks). In the schedule shown in figure 2-4, all maintenance scheduled for Mon- day was completed, but Williams was unable to complete the scheduled requirement M-3 for Tuesday, and the action is rescheduled for Thursday of the same week.

THE MAINTENANCE REQUIREMENT S^o<?;~'^^^ Maintenance Requirement Card (MRC) 5 by 8 inches, has the planned main- tenance task defined in sufficient detail to en- able assigned personnel to perform the task (see fig. 2-5), A master set of MRCs is main- tained in the departmental office and those ap- plicable to the equipment with which you are concerned are maintained in your working space. If a card in the working space be- comes lost or mutilated, a new card can be made from the master set and used until a feedback report is sent in and a new card ob- tained.

The MRC is one of the primary tools of the PMS with which you will be concerned. Sup- pose that on a Monday morning Dwyer looks at the weekly schedule and finds that he is assigned

the maintenance action identified as M-1. The weekly schedule indicated that this particular maintenance action is listed on page T-3 of the PMS Manual. The MRC which describes the task assigned is identified by the number combination T-3 M-1 in the upper right-hand comer. In preparation for performing the as- signed task, Dwyer would pull MRC number T-3 M-1 (fig, 2-5) from the set of cards in the working space.

The MRC identifies the component involved- gives a brief description of the maintenance requirement; lists the safety precautions to be followed; and lists the tools, parts, and ma- terials needed to accomplish the task. This in- formation is listed to enable you to be ready to perform completely the prescribed mainte- nance prior to actually working on the equip- ment involved. The procedure listed on the MRC IS standardized and is the best known method of performing that particular task. Any related maintenance requirement listed on the MRC should be done at the same time or in conjunc- tion with the assigned task for the purpose of time conservation.

The 16-digit number on the lower right- hand side of the MRC is the bureau card control number which can also be found on the MIP. Each MRC has a bureau card control numberj which must be referred to in any correspondence concerning the card.

14

Chapter 2 -MAINTENANCE

Communications and Control

Test Equipment

COMPONENT

AN/USM-105A, 105V Oscilloscope

RELATED M f

None

,1,R. DESCRIPTION

1. Verify speed of blower motor.

TOTAL M/H.

0.1

ELAPSED Til

0.1

SAFETY PRECAUTIONS

1. Observe standard safety precautions.

rOOLS. PARTS, MATERIALS. TEST EQUIPMENT

1. Stroboscope, TS-805A/U or equivalent

1. Verify Speed of Blower Motor.

a. De-energize the oscilloscope.

b. Remove air filter from rear of cabinet.

c. Energize stroboscope and adjust to measure 1750 rpm

d. Energize the oscilloscope.

CAUTION: Do not operate the oscilloscope longer than necessary to perform step c with filter removed.

e. Measure speed of blower motor using the strobos- cope.

NCTTE: If speed of motor has dropped to 1600 rpm, or

less, the motor should be disassembled, cleaned, and lubricated.

f. Return equipment to normal condition.

Date

2 August 1965

98.176 Figure 2-5.— Maintenance requirement card.

On some ships, two or more divisions may have identical equipment. When this occurs, each division will have separate (but identical) MRC cards for the equipment.

Feedback Report

The PM3 Feedback Report, OPNAV Form 4700-7 (fig. 2-6), is designed to report any discrepancies or suggested improvements in the PMS as installed aboard ship. The report is to be filled out by the man who discovers the discrepancy or suggests an improvement, signed by anyone designated by the commanding officer, and mailed via the type commander to the ap- propriate field office listed on the reverse side of the originator's copy of the form. Atlantic

Fleet ships use the Norfolk address and Pacific Fleet ships use the San Diego address.

When submitting a feedback report, be sure it is filled out completely and legibly. Hand- written copies are acceptable but a ballpoint pen must be used to ensure that all copies are legible. Instructions for filling out the feed- back report are listed on the back of the form and are discussed here for the purpose of clari- fication. w^n'^.;

You are required to complete the TO line with the appropriate (San Diego or Norfolk) address. In the "FROM" line insert the hull number of your ship (DDG 11, DD789, AD 36, etc.)- and in the "VIA" line indicate the type commander. The date will be the day you dis- cover the discrepancy or suggest an improve- ment. The serial number indicates the number of feedback reports sent in by your ship. If your ship has previously forwarded five feed- back reports, the next report will be numbered

The blocks concerning the system, sub- system, component, M.R. number, and the bu- reau card control number should be filled in with information from the appropriate MIP and/or MRC. If the MRC or MIP is missing and the bureau card control number is not available, the equipment should be identified by its name and its APL/CID or AN number. The APL/CID number identifies the parts list for the equipment and is found in the index to the Coordinated Shipboard Allowance List (COSAL). The "Technical Publication" block in the "Discrepancy" section of the report is intended to include all Naval Ship Systems and Naval Ordnance Systems Command publications. In the event that any of these are in error, identify the publication number, volume, revi- sion, date, change number, page paragraph, and/or figure.

Prior to the distribution of the report (as indicated on the original and each of the four carbon copies), check it for completeness. The discrepancy should always be explained clearly and a suggestion for its correction must always be offered.

THE MAINTENANCE DATA COLLECTION SYSTEM

The Maintenance Data Collection System is designed to provide a means of recording main- tenance actions in substantial detail so that a great variety of information may be collected

15

ELECTRONICS TECHNICIAN 3 & 2

FROM: DD-712

INSTRUCTIONSITN BACK OF GREFN PAr,F

''"O: Buships/Buwep$ Maintenance Management Field Office Norfolk, Virginia 23511

SERIAL #:

nATF Auguat 16. 1967

VIA:

Go m OuDe sLant

SUBJECT: PLANNED MAINTENANCE SYSTEM FEEDBACK REPORT

SYSTEM,

Conuoinication and Control

SUB-SYSTEM

Teat St^uipnent

DISCREPANCY

5J M. R. Description [_J Safety Precautions □ Tool., Etc.

I [ Missing Maintoinance — Requirement Cord (MRC)

COMPONENT

iiK/USM-lOSA, 1057 Oscilloacope

M.R. NUMBER

T-3 M-1

BU. CONTROL NCU„ ^ _

1?T 290A TG285 BA39 M

D Equipment CUnge Q Typographical

r— j Missing Mointoinonce p-, Teehnicol

Index Page (MIP) U p„blico,ion.

Q Teehnicol Q Miscellon«,u. I— J Procedure

Mac prodedure ia to adjust atroboacope to measure blower motor apeed at 1750 EPM.

Ali/Ua<-105A aboard has Pie Id Change H, requiring a blower motor apeed of 2400 flPM.

aecoaaaend rewording of MRC procedure:

Item #l.c, - Energize stroboscope and adjust to measure 2400 BPM.

NOTE: If speed of motor has dropped to 2250 BW or less, the motor should be disassembled, cleaned, and lubricated.

OPNAV Form 4700/7 (10-65)

Figure 2-6.— PMS Feedback Report, OPNAV 4700-7.

16

40.101

Chapter 2 -MAINTENANCE

cncerning maintenance actions and the per- Irmance of equipment involved. In addition, t9 system provides data concerning the initial cscovery of a malfunction, how the equipment ralfunctioned, how many man-hours were ex- jnded, which equipment was involved, what ipair parts and materials were used, what de- lys were incurred, the reasons for delay, and te technical specialty or work center which irformed the maintenance.

Codes must be used in recording maintenance j;tions in order to allow converting the informa- «)n to a language that can be read by automatic (.ta processing machines. As a third or second cass Electronic Technician, you will be required t fill out various maintenance forms, using the odes listed in the Equipment Identification <5de (BIC) Manual. The forms are sent to a «ita processing center where the coded infor- lation is punched into cards which are machine j-ocessed to produce the various reports for ise in maintenance and material management. The reports that are produced by the auto- atic data processing machines will be ac-

curate and useful only if the information is clearly and accurately entered on the main- tenance forms. Therefore it is very important that the codes which you enter on the forms be accurate and clearly written.

Maintenance Data Collection System Forms

The MDCS forms on which you may be re- quired to make coded entries include OPNAV Form 4700- 2B (Shipboard Maintenance Action), OPNAV Form 4700-2C (Work Request), and OPNAV form 4700- 2D (Deferred Action). De- tailed descriptions of the entries to be made on these forms are listed in the EIC Manual and in chapter 3 of the 3-M Manual (OPNAV 43P2). Brief descriptions of these entries are also listed here to help you become familiar with the forms, which are shown in figures 2-7 through 2-10.

Block A, Ship Name and Hull No. /Activity: Enter the name and hull number of your ship— for example, USS Now (DD 746).

MAINTENANCE DATA COLLECTION OPNAV FORM 1700-26 (8-61'

SHIPBOARD MAINTENANCE ACTION

F, OeSCR I PT I ON/REMARKS

Br-14 open. Replaced

17.81B

Figure 2-7.-Shipboard Maintenance Action, OPNAV 4700-2B(8-64).

17

ELECTRONICS TECHNICIAN 3 & 2

MAINTENANCE DATA COLLECTION OPNAV FORM 4700-2D <e-Q4}

DEFERRED ACTION

A. SHIP NAME AND HULL NO. /ACTIVITY

USS HOW DD-74S

5. EQUIPMENT ID COOEl

6 W.C..

0 I SI T

7. ASSI. W.C.

14. SERIAL NO.

1 I- |6|4|-|2

F. DESCRIPTION/REMARKS

DC Drive Motor failed during operation. Investigation indicated armature winding burned out. No rewinding facilities onboard.

Figure 2-8. -Deferred Action, OPNAV Form 4700-2D (8-64), sheet 1.

17,81D

Block 1, Administrative Organization: Enter the 4-letter/number code (from section 11 of the EIC Manual) to which your ship is assigned (if your ship is assigned to DESRON 7, you would enter D070).

Block 2, Unit Identification Code (UIC): Enter the UIC number for the ship or activity for which the maintenance was performed. This entry is obtained from NavCompt Manual, Vol- ume 2, chapter 5.

Block 3, Maintenance Control Number: This number is used to relate all documents sub- mitted on a specific job and is filled in by the maintenance control section of your ship before the documents leave the ship. The numbers will be assigned consecutively beginning with 0001 and ending at 9999. Upon reaching 9999, the series will be started again at 0001.

Block 4, Date: Enter the day, month, and year the maintenance is accomplished; or, for a work request, enter the date the request is submitted.

Block B, Type Availability: This block is left blank on all forms except the Work Request,

OPNAV Form 4700- 2C. On the work request, this block will be filled in with a single- letter code, taken from section IX of the EIC Manual, to identify the type of availability in which the repair activity will perform the mainte- nance.

Block 5, Equipment Identification Code: Enter, from section X of the EIC Manual, the appropriate 7- letter/ number code which iden- tifies the system, subsystem, component, and/or lowest designated assembly on which mainte- nance is requested or performed. Caution must be exercised to ensure that the EIC number correctly identifies the exact item on which maintenance is requested or performed.

Block 6, Work Center: Enter the 3-letter/ number code from section III of the EIC Manual which identifies the department, rating, shop, or group which performs the maintenance ac- tions on the equipment identified in the equip- ment identification code, block 5.

Block 7, Assisting Work Center: Leave blank. When information is required in this block it will be filled out by your supervisor

18

Chapter 2 -MAINTENANCE

MAINTENANCE DATA COLLECTION OPNAV4700-2C <6-64i

WORK REQUEST

F. DESCRIPTION/REMARKS

1. Motor, D.C. Drive

2. Armature winding toumed out

3. Eewind, dip, bake and turn down coiomutatorg.

FOR LOCAL USE ONLY

'^:°&Z^J^ ^r/

NO 2 CONTAC/ \

^7-/

17.81C

Figure 2-9.-Work Request, OPNAV 4700-2C (8-64).

in accordance with the EIC Manual and chapter 3 of the 3-M Manual.

Block 8, Repair Activity Unit Identification Code (UIC) obtained from NavCompt Manual, Volume 2, chapter 5.

Block 9, How Mal/MRC: If the action is a result of a malfunction, list the 3- digit code from section IV of the EIC Manual which best describes the trouble. H the action is planned maintenance (MRC), enter a 3 -letter/ number combination code which identifies the frequency check on the equipment. For example, if the situation is an M-1 PMS action, enter MOl. For all other actions three zeroes (000) will be entered.

Block 10, Discovered: Enter the appro- priate code from section V of the EIC Manual which identifies when the maintenance require- ment was discovered.

Block 11, Action Taken: Enter the code from section VI of the EIC Manual which best describes the maintenance action taken. "Not Repairable This Ship" (NRTS) codes will be used only by repair activities.

Block 12, Units: Enter the number of iden- tical items, identified in block 5, on which the same maintenance action was attempted, per- formed, or requested. If identical alterations or significant maintenance actions are accom- plished on identical equipment bearing different serial numbers, each equipment will be reported on a separate document.

Block 13, Man-hours: On completion of the maintenance action, enter the total man- hours (to the nearest tenth) expended by all shipboard personnel. If the task was com- pleted in 1-1/2 hours, for example, you would

'0015". Enter a "0" in any space not Blank: Leave blank, (explained

enter used.

Block E, later). ,

Block 14, Serial Number: When several equipments aboard a ship have identical EIC's, Block 14 is used to identify the specific equip- ment on which maintenance is performed. This information is required for accountability at the System Command level and for equipment his- tory purposes at the local level. Serial numbers

19

ELECTRONICS TECHNICIAN 3 & 2

will be used for electronics and ordnance equip- ments. For example, the serial number of the radar, the radio, the computer, or the test equipment will be reported; the serial num- bers of the major components of these equip- ment, however, will not be reported even though all work is done in a component such as a radar transmitter assembly.

Blocks 15 thru 19 (block 19 not shown) apply only to OPNAV 4700-2C, Fig. 2-9.

Block 15, T/A: Leave blank.

Block 16, Requesting Work Center: Enter the letter/ number code that identifies the depart- ment, rating, shop, or group that is requesting assistance from the repair activity. Work center codes may be foundinsectionlHofthe EIC Man- ual.

Block 17, Desired Completion Date: Enter the day, month, and year that the outside repair activity must complete maintenance in order for the requesting activity to meet its operational commitments. If this date were 28 Aug. 1967, for example, you would enter 28087.

Block 18, Service: Enter the single-letteii code from section VII of the EIC Manual which identifies the type of assistance the requesting- ship will furnish the repair activity in complet-i ing the requested maintenance.

Block 19, Scheduled Start Date: This entry,; which is for repair activities only, is the es-i timated starting date of the requested mainte-x nance. -

Block D, Leave Blank.

Block E and 20, Equipment Downtime anc; Equipment Operating Time: These entries are; required only for equipment identified by greens pages in the EIC Manual. Detailed instructions! for these blocks may be found in section I ot: the EIC Manual and chapter 3 of the 3-M Manuals

Block 21, Alteration Identification: If am alteration is to be accomplished, this block willi contain the alteration identification from the authorization directive.

The Shipboard Maintenance Action Formi (fig. 2-7) (OPNAV Form 4700- 2B) is a single- .■ sheet document used to record the completion,:, of planned maintenance actions, corrective-

ki

MAirTTENANCE DATA COLLECTION OPNAV FORM 470O-2D 16-04}

DEFERRED ACTION

SHIP NAME AND MULL NO. /ACTIVITY

U33 ilOW S0.746

1. ADMIN. ORG

» 10 17 10

2 SHIP ACCTO NO.

0 |3|e |g|i

3. MAINT. CTRL. NO

0 111 7 e

»■ 9 ! 0| 8i 7

>'■/ '//■^,"-'/'///r/7/-/y//y/^

''^t'" ^%^4^r^f-

9. EQUIPMENT iD CODET

P jB |0|1 |0|7^

6 W.C.

0 1 »T

4. SERIAL NO.

1 t- |6i4l-|2|

F. DEsdaiPTION/REMARKS

B. REPAIR ACT. ACCT. NO.

20. EOUIP/TIME

e. MAL/MRC.

0 18 10

12. UNITS

Oil

13. MANHOURS

0| 0|4 IS

21. ALTERATION IDENTIFICATION

DC Jrive Motor failed daring operation. Inrestlgatlon Indicated an^ture winding burned out. Ho rewinding facilities onboard.

aewound by USS frontier AI>.25, tested and returned onboard, installed onboard 29/8/67; operation is satisfactory.

Figure 2-10.-Deferred Action, OPNAV 4700-2D (8-64), sheet 2

20

Chapter 2 -MAINTENANCE

„intenance actions and authorized alterations tit have been performed at the shipboard level fc shipboard personnel. All planned mainte- nnce actions except daily and weekly planned riintenance actions must be recorded on this frm in addition to checking them off on the \!ekly and quarterly schedules. Routine pres- evation such as chipping, painting, and cleaning ould not be reported.

Any corrective maintenance actions that are

[f erred because of the ship's operations, lack

repair parts, or the requirement of outside

isistance are reported on the Deferred Ac-

in Form (fig. 2-8)(OPNAV 4700-2D). The

1.-st sheet of this 2-sheet document is used

1 record and report the reason for deferral

Slid the second sheet is used to report the

ompletion of the maintenance action. If a

orrective maintenance action must be de-

irred, this form is required at the time a

malfunction is noted. A sample sheet 1 of the

ieferred Action Form which could have re-

lalted is shown in figure 2-8. The action taken

lode, block 11, and the man-hours expended,

lock 13, on sheet 1 of the Deferred Action

orm apply only to the action taken man-hours

.volved at the time of the discovery of the

lalf unction.

Figure 2-9 shows a Work Request (OPNAV orm 4700-2C) to have the motor starter re- ound. In completing block F (Description/ emarks) of the work request, note that:

1. The component must be identified by

.me.

2. The CID number of the component must

listed.

3. The alterations number must be given, applicable. If not applicable, it must be

isted as N/A.

, 4. A description of what is wrong with the Equipment and what you desire the repair ac- tivity to do must be given.

I The signature blocks G, H, and J are to be ■ igned by three leading petty officers, one from ach duty section, who are familiar with the Tork to be done by the repair activity. Signa- ure block K will be used by the commanding fficer or his authorized representative to in- icate command approval of the request for epair assistance.

(After the repairs have been completed by he repair activity, "sheet 2" of the Deferred action Form (fig. 2-10) is completed by enter- ; ng the date of completion in block 4, the action aken code in block 11, the additional man-hours

in block 13, and appropriate remarks in block F. The form is then signed by the man doing the work and by his supervisor, and is then sub- mitted to the data processing center.

The information contained in blocks A, 1 and 2 of OPNAV Forms 4700- 2B, 4700- 2C, and 4700- 2D will be identical on all forms for any particu- lar ship; if desired, this information may be preprinted in by the ship. Each maintenance action is assigned its own unique maintenance control number; if a maintenance task requires more than one form, as in the example using figures 2-8 through 2-10, the numbers will be identical.

Personnel attached to repair activities are required to record certain information on a Work Supplement Card (not shown) for each repair job. Work supplement cards will be explained to you by your division petty officer if you are assigned to a repair activity.

Material Usage and Cost Data

The documentation of material usage and cost data on maintenance transactions requires the joint effort of the supply and maintenance personnel on board your ship. Economy of ef- fort and the elimination of duplicate recordings are highly desirable.

Any time that repair parts or materials are drawn from the supply department for shipboard maintenance, a NAVSANDA Form 1250 is used to request the materials from supply. Mam- tenance personnel are required to furnish the work center code and the EIC taken from the EIC Manual, the component identification (CID) number, the maintenance control number, the name of the part, quantity required, and the stock number when submitting this form to the supply department. The supply personnel will then complete the form; the cost is documented from this form if the ship does not have data processing equipment aboard. If the ship has data processing equipment, a DD Form 1348 is used instead of the Form 1250.

When the material to support a maintenance action is obtained from outside the normal supply channels or from pre-expended material bins, the reverse side of the appropriate OPNAV form (OPNAV 4700- 2B, 4700- 2C, or 4700- 2D) is used. The reverse sides of OPNAV 4700 series forms are essentially the same. The reverse side of OPNAV Form 4700-2B is shown in figure 2-11. On this side of the form, when appropriate, you will enter the CID number, the

21

ELECTRONICS TECHNICIAN 3 & 2

T

CID/	iPL/AEL/4N S'S^7(:>/0|
CODE	:o:-	ETEPAL STOC", NO-/PART NO.	RETERENCE SYMBOL ■ NOuN	MATERIAL PEO. UMTS 1 &',*NT,T.	MATERIAL '.SE:.	UNIT PR ICE
/	/V	^ oS'AS^-oo^'f■	^/v^/r		EAs i)^	.j/

OPNAV FORM '*700-2B (8-6t) BACK

Figure 2-11. -Reverse side of OPNAV 4700-2B.

17.81BCD

source code taken from section Vm of the EIC Manual, the cognizance symbol taken from supply publications to identify the supply account and the inventory manager of the item used, the Federal Stock Number, the reference symbol taken from circuit diagrams or the name of the part being replaced, the unit of issue of the material used, quantity used, and the unit cost (except on pre- extended material) of the item.

THE MAN-HOUR ACCOUNTING SYSTEM

The Man-hour Accounting System, some- times referred to as Exception Time Account- ing (ETA), is designed and intended for use by repair activities in conjunction with the Main- tenance Data Collection System. It is basically a management tool and accounts for deviation from a normal working day.

As a third and second class petty officer as- signed to a repair activity, your only concern

with this system will be when you are absent! from your assigned working space for more; than 20 minutes at a time. If this occurs, , your leading petty officer will hand you a Daily) Exception Card on which you will be required to fill in the date of change and the number of I hours concerned to the nearest tenth of an hour, , and then return the card to your supervisor. . In the example card shown (fig. 2-12) Jones, , K, P., ET3 (004 code) assigned to the electronics) repair shop (67A code) for direct labor (01 code) was absent for one and a half hours. This absence was to take care of personal . affairs and is therefore a non-duty absence as shown by the reverse side of figure 2-12,

MAINTENANCE HISTORY REPORT

The Maintenance History Report (MDC-5) will serve as a record of equipment history. Figure 2-13 shows an example of the Mainte- nance History Report (MDC-5) which will be received by each ship on a monthly basis.

22

Chapter 2-MAESrTENANCE

67A

JUj<j.S. k.p.

NAME (LAST a INITIALS)

CflTfR ASSICKD

TYPE OF CHANGE (V) I I X SHORT TERM LOAN TO:

WORK CENTER CODE

I I 1. ASSIGNED

I I 2. TRANSFERRED

rXl 3. LABOR CODE

I I 8. OVERTIME

DATE OF CHANGE f HOURS OF CHANGE

10 09 J^ 1 5

DAY MO YR

004

01

CHANGE LABOR CODE TO"- IV)

PRODUCTIVE DIRECT

I I 01 DIRECT LABOR

PRODUCTIVE SUPPORT

□ ,_ MAINTENANCE ADMIN. '" a SUPERVISION

I 1 11 l»(ATERIAL CONTROL

□ ,, TENDER EQUIPMENT ''^ MAINTENANCE

□

SUB CODE

ACCURACY HEXPS MAINTENANCE

utson

c»oe

TENTHS OF HOUR KEY

1-2

9-14

15-20

21-26

27-33

34-39

40-45

46-51

52-57

58-60

FULL HI

NON-PRODUCTIVE

I I 20 DELAYS

I I 21 DUTY ABSENCE

I I 22 NON DUTY ABSENCE

[X] 22.2

SUB CODE

J 15 IS IT li li ;n 11 :: :

75 n if n a M 3i 3: n M IS K i' ^ 1^ *3 «' " *-* ** *

L^.JVl

10 III

CEHIEI

H LASOtt

CODE

FRONT SIDE

NAME tLAST a INITIALS)

GRADE

cooe

t, ^ ts 5f a s-i'ii li ti :, ti Si 5t «i: u 6i.[0ji ::? -J ■* 'Ji :5 " » ^ '^

LABOR SUB-CODES

PROOUCTIVE SUPPORT

10 1 Work Center Supervision

)0 2 Wortlood Plonmng/Contrrt

10 3 Clerical

104 Drafting

10 5 Anolysis

10 6 Mointenance Technicol Tramirtg

12 I Ship EquipmenI Mointenance

12.2 Repoir/Weapon's Dept. Equip Momt

!2.3 Repoir/Weopon's Eqjip. Cleoninq a Preservotion

201 flwoiling Work

202 Awaiting Porls/Maleriol 20.3 Awoitiog Tronsportotion

204 Awotting Assistonce

205 Inclement Weather

DUTY ABSENCE

21.1 Quarters for Hu*ter/Sp«cial Sea

Detail

21.2 Department Waicn 21 3 Ship/BoM Wolch 2)4 Condilion Watch

21.5 Ifclitory Troimng

21.6 TAD

217 Mess Cooks /Compt Cleoners

21.8 Vehicle/Boot Operolions

21.9 Personnel/Zone Inspection

NON-DUTY ABSENCE

22.1 Me<ficol Absence

??? Persoool Affoirs

22.3 Leove

22.4 Special Liberty

22.5 Uoouthorized Absence 22-6 Confinement

227 Non-Judictol Punishment

REVERSE SIDE

17.81E

Figure 2- 12. -Daily Exception Card, OPNAV 4700- 2E (1-65).

The report provides a comprehensive main- enance manhour and material history of all .ctions (different MCNs) received from a re- jorting activity monthly. It embodies a three te- ine printout with the first line basically iden- tx ifying the maintenance action and manhours iharged, the second line, equipment time and

intermediate repair activities, and the third, line material usage. The report is organized at the EIC equipment level and is further sum- marized at the subsystem and system levels. Ship totals for actions, active maintenance time, and manhours are also included. The report is a basic tool for the analysis of recurring

23

ELECTRONICS TECHNICIAN 3 & 2

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2		LU	LU	■^		P^

24

Chapter 2 -MAINTENANCE

equipment and structural maintenance problems n terms of both manhour and material usage, n addition to furnishing a monthly recapitula- ion of equipment history.

When fully implemented the PMS and MDCS lystems are intended to supercede any other •ecords or reports previously required under ither maintenance systems. In the meantime, ihips and stations will find they have to operate inder several systems simultaneously. It is or this reason that the other maintenance sys- ems, such as POMSEE and CSMP, are explained n this chapter.

A good explanation of which system to use, it you are in the middle of a changeover, can je found in EIB 707 of 27 May 1967, and by reference to type commanders' instructions, [t is anticipated that some of the forms pre- iriously described will also be changed before he system is fully implemented throughout the (Javy, so it is a good idea to always check the atest EIB for up to date information regarding naintenance procedures.

MAINTENANCE STANDARDS BOOKS

Tests and maintenance procedures pre- scribed in the Maintenance Standards Books provide maintenance and operation personnel with systematic and efficient methods for check- ing equipments and for performing scheduled preventive maintenance. These books contain a series of reference standard tests (fig. 2-14). These tests, when performed on properly op- erating equipment, provide quantitative results (reference standards), which collectively repre- sent the design performance of the specific serial numbered equipment or system for which the book is assigned. When these tests are ac- complished as scheduled (weekly, monthly, quarterly, etc.), the test results are compared against the reference standards to determine the condition of the equipment. Charts (time schedules) are provided for logging the results of each test so that a performance history of the equipment can be developed (fig. 2-15). In addition to these functional tests, the book also contains the specific procedures and sched- ule necessary to provide for mechanical and electrical maintenance for the equipment or system (fig. 2-16).

The maintenance checkoff is gradually being superseded by the Planned Maintenance Sys- tem. If the Planned Maintenance System (PMS) portion of the 3-M system has been implemented,

recording under the POMSEE program is no longer a NavShips requirement. This does not mean that the Maintenance Standards Books can be discarded: Maintenance Standards Books must be retained to make up a complete series of records, even though no new entries are to be made. Directives as to exactly which records are required are promulgated by type com- manders, or similar level for shore activities.

PERFORMANCE STANDARDS SHEET

The Performance Standards Sheet (fig. 2-17) establishes the standards for the optimum per- formance of the equipment which must be met upon installation. The sheet contains a table of standards (table I), for operational per- formance and a list of standards for equipment measurements (table II). The information on the sheets may be used as the basis for accept- ance tests and electronics material readiness inspections.

The standards for operational performance is a tabulated nontechnical description of satis- factory equipment performance which could be tables of expected radar ranges of detection, maximum radio ranges, and voltage ranges. The operational performance values are ob- tained from design data and by actual field measurements under normal conditions while the equipment is operating satisfactorily in the location of its intended use.

Special information relative to such op- erational performance as range and bearing accuracy and discernible characteristics of sig- nals may be given on the performance standards sheet in another table. This special informa- tion is obtained from actual measurements as well as from design data.

The list of standards for equipment meas- urements, Table H, provides a record of meas- urements (standards) that indicates satisfac- tory overall equipment performance. The test results entered in the Maintenance Standards Book may be compared at any time with the data given in the Performance Standards Sheet to determine if the equipment or system meets the standards as specified.

TECHNICAL MAINTENANCE

Technical maintenance is normally limited to maintenance consisting of replacing unserv- iceable subassemblies or parts and the align- ment, testing, and internal adjustment of equip- ment.

25

ELECTRONICS TECHNICIAN 3 & 2

QUARTERLY STEPS "^iV thru YqsV

NAVSHIPS 947 15.42

AN/WRR-2, -2A AN/FRR-59, -59A

OPERATING CONDITIONS AND CONTROL SETTINGS:

Equipment in full operation and conditioned for Al reception O. L. THRES: OFF

ACTION REQUIRED

Record over-all sensitivity of Mode Al at low end of 2-4 mc band.

READ INDICATION ON

Signal Generator AN/URM-25

REFERENCE STANDARD

(1.5 max. ,

*PROCEDURE: Connect signal generator to the ANT IN jack (J957) Adjust rA*;^^'"^ ^ ^'""^ ""'"adulated signal and set output at 5 ^v. Set

fnd Sp^inr"' '° ^^\ ■^""^ receiver to 2 mc and adjust the ANT COMP ana tit AUJ controls for maximum indication on the RESONANCE meter ^^•^'^^e^'^^ratoT output to zero and adjust RF GAIN for a - 2 db indication on the LINE A OUTPUT meter. Set generator output to 5 ^v and adjust generator frequency for a maximum indication on the RESONANCE meter. Readjust generator output for a +18 db indication on the LINE A OUTPUT meter. Record the generator output in microvolts.

Repeat for high end of band.

Signal Generator AN/URM-25

(1.5 max. )

PROCEDURE: Tune receiver to 4 mc and repeat step Ql.

Record over-all sensitivity of Mode Al at low end of 4-8 mc band.

Signal Generator AN/URM-25

(1.5 max. )

PROCEDURE: Set BAND selector to 4-8. Tune receiver to 4 mc and repeat step Ql. ^

Repeat for high end of band.

Signal Generator AN/URM-25

[l.i max. )

PROCEDURE: Tune receiver to 8 mc and repeat step Ql.

Record over-all sensitivity of Mode Al at low end of 8-16 mc band.

Signal Generator AN/URM-25

(1.5 max. ,

PROCEDURE: Set BAND selector to 8- 16. Tune receiver to 8 mc and repeat step Ql. '^

Repeat for high end of band.

Signal Generator AN/URM-25

pv

(l .5 max. )

PROCEDURE: Tune receiver to 16 mc and repeat step Ql.

Record over-all sensitivity of Mode Al at low end of 16-32 mc band.

Signal Generator AN/URM-25

(1.5 max. )

PROCEDURE: Set BAND selector to 16-32. Tune receiver to 1 6 mc and repeat step Ql. ^

Repeat for high end of band.

Signal Generator AN/URM-25

(1.5 max. )

PROCEDURE: Tune receiver to 32 mc and repeat step Ql.

Figure 2-14. -Sample page from Maintenance Standards Book, reference standards tests.

26

36.100 1

Chapter 2 -MAINTENANCE

TIME SCHEDULE QUARTERLY STEPS

YqiY thru'^Sy

"^igT" and "^2^

TIME SCHEDULE: Record and initial.

NAVSHIPS 94715.42

AN/WRR-2, -2A AN/FRR-59, -59A

1ST YEAR OF OPERATION

1. Date	2. Date	3. Date	4. Date
No.	(IV	Init.	No.	KV	Init.	No.	(IV	Init.	No.	M-v	Init.
^
tl
^
^
^
^
^
^

1ST YEAR OF OPERATION

1. Date	2. Date	3. Date	4. Date
No.	kc	Init.	No.	kc	Init.	No.	kc	Init.	No.	kc	Init.
^
1^

36.100

Figure 2-15.— Sample page from Maintenance Standards Book, time schedule.

27

ELECTRONICS TECHNICIAN 3 & 2

AN/WRR-Z, -2A AN/FRR-59, -59A

NAVSHIPS 94715.42

UNSCHEDULED (us) thru fuTo)

OPERATING CONDITIONS AND CONTROL SETTINGS:

Equipment de- energized.

AC power plug (P1808) removed from POWER IN jack (J1808).

Drawers extended lin turn) from cabinent.

Decks tilted or separated to gain access.

STEP NO.

ACTION REQUIRED

Clean equipment

PROCEDURE: Clean cabinets and chassis with vacuum cleaner. Check air filter; clean and recharge if necessary (see Quarterly Step Q29).

Perform mechanical inspection.

PROCEDURE: Note action of drawer mechanisms. Operate all controls, observing mechanical action. If control stick or binds DO NOT FORCE MOVEMENT. Find the cause (bent shaft, loose mounting, etc. ) and correct it. Observe action of counter mechanisms and all gearing. Note condition of lubricant and replace if necessary. Turn blower fan by hand, observing freedom of rotation. Inspect switches for arcing damage. Burnish contacts by rotating switch, if necessary. Lock all tube shields and/or tube clamps.

Perform electrical inspection.

PROCEDURE: Inspect all electrical components, wiring and cabling. Look and feel for loose connections, kinks, strain, and damanged insulation; correct defects or report them to a qualified technician. Look for evidence of overheating; take corrective action if any is found. Replace bulging or leaking capacitors, after first removing any residue.

t,. o ^o 36.100

Figure 2-16.-Sample page from Maintenance Standards Book, preventive maintenance steps.

CORRECTIVE MAINTENANCE PROCEDURES

To perform effective corrective maintenance the ET must have a good working knowledge of the basic principles of electricity and elec- tronics. The only way to acquire this knowledge is by diligent study. The ET must also be thoroughly familiar with the theory of operation of the equipments that he must service. A knowledge of the theory of operation can be acquired through a study of the equipment instruction book. This knowledge should be broadened to include other equipments at the earliest opportunity. As a matter of fact, ETs are generally rotated on the various elec- tronic equipments so that their knowledge will be broadened and they will therefore be more valuable to the fleet.

Skill in the use of test equipment (and hand- , tools) is also necessary for effective corrective i maintenance. Skill in the use of test equipment il comes with practice and with careful study of the instruction book that comes with each piece of test equipment. The ET should take advantage of every opportimity to learn more about every, type of electronic test equipment used aboard] ship. The ability to use test equipment effec- ■ tively is an absolute must for every well-trained ET.

Chapter 3 of this training course introduces some of the special type test equipments. Ad- ditional valuable information (both on test equip- -^ ment and methods of troubleshooting) is con- fe tained in Test Methods and Practices. NavShips ^ 900,000.103, J

Tests (opens, grounds, and shorts) and meas- 1= urements (currents, voltage, resistance, fre- - quency, power, etc) enable the technician to

28

Chapter 2 -MAINTENANCE

6 April 1964

NAVSHIPS 94715.32

AN/WRR-2,-2A AN/FRR-59, -59A

PERFORMANCE STANDARD SHEET for RADIO RECEIVING SETS AN/WRR-2. -2A, AN/FRR-59, -59A

TABLE I - OPERATIONAL PERFORMANCE

The many variables involved, such as radio propagation conditions at the time of the test, power output of the transmitter being received and the type of antenna installation, preclude definitive predictions of oP^ation ranges To achieve optimum reliable ranges, frequency selection should be made m accordance with DNC-14, as corrected by half-hourly radio propagation pre- dictions given over WWV and WWVH.

TABLE II - STANDARDS FOR EQUIPMENT MEASUREMENT

MEASUREMENT

Bandwidth [IF, 1.0 kc)

Receiver Sensitivity (Sr)

Performance Figure iPFJ *

STEP

Q19 and Q20

Ql thru Q8

Calculate

STANDARD

0.8 kc min. (at 6 dbj 2.4 kc min. (at 60 db)

1.5 H-v max.

1.5 max.

* PF = Sr (tiv)

Total time required to perform Table II measurements - 1 hour.

All steps refer to tests in the Maintenance Standards Book, NAVSHIPS 94715.42

This Performance Standards Sheet supersedes NAVSHIPS 93 550.3 2

Figure 2-17.— Performance standards sheet.

liagnose troubles so that repairs may be made. n many instances tests and measurements will adicate conditions that may be corrected before 1 actual breakdown occurs. Thus, tests and measurements (particularly measurements) are mportant both in preventive and corrective aintenance.

36.100

The purpose of any type of electronic test equipment is to measure accurately certain circuit values or to indicate certain circuit conditions. Each of these measurements or indications is used to determine the operating condition of electronic or electrical equipment. The accuracy Avith which measurements are

29

ELECTRONICS TECHNICIAN 3 & 2

made depends on the type of instrument used, its sensitivity, its rated accuracy, its useful range, and the care that the technician uses in making the measurement.

The exact procedure for making tests and measurements is given in the technical man- uals (instruction books) that accompany the various electronic equipments.

It should be emphasized that the mere tak- ing of measurements means little unless they can be properly interpreted. For example, the presence of a voltage across a grid resistor in an audio amplifier would mean little to an ET unless he could interpret this in terms of a possible leaky coupling capacitor. In this connection, thenecessityfor a knowledge of basic circuit operation must be emphasized.

Before any attempt is made to interpret the results of measurements, an understand- ing of how the equipment operates should be acquired by a careful study of the applicable technical manual or instruction book.

The actual voltage, resistance, and cur- rent measurements that should be obtained are indicated in the circuit diagrams, charts, or in the maintenance standards books. The same is true of waveform measurements. Any de- viation from the standard values (beyond the tolerance limits) means that some component is not doing the job that it should. By apply- ing effect-to-cause reasoning, the defective component may be located. This is, of course, a job for a skilled technician.

Maintenance personnel must try to find the source of the trouble causing the equipment failure, particularly when the trouble is a re- current one. The recurrence of a fault usually indicates that the EFFECT, not the CAUSE, has been remedied.

There are numerous ways to isolate a fault to a component of a system, depending on the type of equipment. The technician must, first of all, know what each component does before he can know that it is not functioning properly. Assume, for example, that the display on a certain radar repeater is faulty. The trouble could be in the repeater or it could be in one of the circuits that feeds into the repeater. If the other repeaters are working properly, it is probable that the trouble is in the re- peater having the faulty display or in its power supply or in the transmission lines or switching system.

The best way (the most economical in time and effort) to isolate a fault is by using a logical troubleshooting method.

Keep in mind throughout this study, that by far the largest section of the average instruc- tion book is the one devoted to corrective main- tenance (troubleshooting). This is the section written especially for the ET and when used with the six- step logical troubleshooting pro- cedure (described later) can be for him the most valuable part of the book. The section on the theory of operation, however, is also very im- portant and should be studied with care.

Good troubleshooting is not a talent with which a person is born. It is, however, a skill that can be acquired by anyone with a suitable electronics background. One can become a good troubleshooter if he has:

1. Sufficient electronic knowledge to learn, or to be taught how an equipment works.

2. Suitable skill in reading and interpreting data contained in the equipment's technical manual.

3. Suitable skill in operating test equipment and interpreting test readings.

4. Learned how to troubleshoot in a logical manner.

Logical troubleshooting is a time-proven procedure used by all accomplished technicians. Most of them have applied the procedure so often that they no longer pay attention to its fine points. Through habit and years of ex- perience they may have forgotten its specific details, but the procedures are there and have remained the same.

Probably no two technicians would explain the procedure alike, but all would agree that logical troubleshooting consists of a series of sequential steps based on valid electronic de- cisions that systematically narrows the trouble down to the faulty part. Some would list the procedure in three or four steps, others would count a dozen, fifteen, or more. Regardless of the number, the principle would be the same. Six steps have been chosen as the easiest method of learning and applying this procedure. The steps in their sequential order are: 1. Symptom recognition

Symptom elaboration

Listing the probable faulty functions

Localizing the faulty function

Localizing the faulty circuit

Failure analysis

2. 3. 4. 5. 6.

30

Chapter 2- MAINTENANCE

SYMPTOM RECOGNITION

The first step in any troubleshooting prob- lem is recognition of a trouble indication. Rec- cognizing a trouble condition in an equipment is not always easy to do since all conditions of less than peak performance are not always apparent. Lack of targets on a scope, timing error in a loran set, and a decrease in signal-to-noise ratio in a receiver are just a few of the hun- dreds of examples occurring throughout the Navy. Each of these is a trouble symptom that requires recognition and elimination.

There are many ways in which the existence of a trouble can be detected by a technician. The obvious troubles will undoubtedly be reported by the operator. These usually include complete or almost complete malfunction of the equipment. Troubles that are not easily noticed are those that cause a gradual decrease in equipment performance. For example, a 125-mile radar that is reaching only 105 miles, a 100-watt transmitter that is putting out only 87 watts, or a multimeter that provides readings that are 10% off, are equipment faults that are difficult to recognize because there are no visible or audible indications (built-in) that say they exist. Since a ship must depend on full-performance equipment, the hidden trouble symptoms must be found, the cause of the trouble located, and the repair made. If the technician makes a point of looking for them every time he touches an equipment most of the decreasing performance symptoms can be easily recognized. Often he can compare the performance between two simi- lar equipments. He can actually make the Performance Standards sheet checks contained in the POMSEE program. By using the POMSEE books, he can verify any change in perform- ance since the last time he tuned, calibrated, or aligned the equipment. Also while trouble- shooting, he may look for and probably find symptoms that signify decreasing performance and future breakdown if left unnoticed. Trouble symptoms can be recognized if the technician will only look for them.

SYMPTOM ELABORATION

Breaking out test equipment and equipment prints and proceeding headlong into trouble- shooting on just the original identity of a trouble symptom is a very shaky premise. It could also be an unnecessary expenditure of energy. A dead scope, a hum in a receiver, a zero reading on a

panel meter, or a missing transmitter pulse, by itself, is not sufficient identification of a trouble symptom. There is a tendency among less efficient technicians to attempt a solution of a troubleshooting problem before they have com- pletely defined it.

The procedures involved are dependent upon the available aids designed in the equipment and the nature of the original symptom. The aids include front panel controls and built-in per- formance measuring indicators. Additional in- formation can be obtained about any malfunction as the result of a systematic front panel check. If the technician has a fair knowledge of how the equipment works, manipulation of appropriate controls and switches and corresponding checks of equipment meters and scopes will reveal to the technician how the trouble is affecting the entire equipment. From these clues he is able to narrow down the probable areas of the equip- ment that could contain the trouble.

LISTING THE PROBABLE (FAULTY FUNCTIONS)

The third step requires that the trouble- shooter make an educated guess as to the prob- able cause of the trouble. From the elements of the trouble symptom, as he has identified it, he determines its most logical locations. Locations are to be confined to the major subdivisions (major or functional units) of an equipment. Educated guesses are made from the knowledge of how the equipment works and a study of the equipment's functional block diagram.

For example, using a malfunctioning radar that has no targets on the PPI but the trans- mitter and modulator indications read good, the educated guesses could include: (a) remote indi- cator unit, (b) receiver unit, (c) low-voltage power supply, and (d) duplexer. Making an edu- cated guess that a tube is bad (just because the greater percentage of all equipment troubles are caused by bad tubes) is not acceptable. The purpose here is to use valid reasoning to isolate all probable, technically sensible func- tional areas which may contain the trouble. It may well be that the specific trouble is a bad tube, but wholesale tube substitution takes a lot of time and quite often introduces addi- tional troubles, particularly in those circuits that operate close to critical tolerances.

Even the accomplished technician may not be able to list all the functional units that

31

ELECTRONICS TECHNICIAN 3 & 2

are probable sources of the trouble. However, with the exception of a very obvious trouble, a multi-unit equipment will have many func- tional units that are probable sources of a trouble,

LOCALIZING THE FAULTY FUNCTION

In this step one of the educated guesses must be selected for testing. It is not neces- sarily the one that was thought of first nor the one that past experience suggests as being the most attractive. The selection of the functional unit to be tested (or verified) first should be based not only on priority of validity but also on the difficulty in making the necessary tests. Under some circumstances, a troubleshooter might elect to test the second best educated guess rather than the first because the latter might involve testing difficulties that should be initially avoided or require tampering with circuit parts that might later prove to be un- necessary. Like all the others, this step in the troubleshooting procedure places emphasis on common sense thinking rather than the resultant action.

After selecting the order in which the listed units will be checked, the troubleshooter pro- ceeds to verify his first selection. This check normally is made at the output test point of the suspected unit. The test equipment reading is compared with the desired signal contained in the technical manual. No output is relatively easy to recognize. A distorted or nonstandard output, however, should be carefully verified before arriving at a technical conclusion.

If the technician does his mental work prop- erly, manual work in gaining access to test points and using the test equipment can be Um- ited to a bare minimum. This procedure is op- posed to trial- and- error methods where the technician searches from point to point with test prods, hoping to locate the faulty test reading that identifies the trouble. Not only does the illogical technician waste valuable time, but his unwillingness to rely on his technical knowledge indicates that he will be very lucky if he finds the trouble.

Upon completing the verification of the prop- able faulty unit selected, the technician will have arrived at one of several conclusions. The test may verify that this is the unit in which the trouble lies; or that the trouble could be in this unit plus another unit(s) from which it

receives signal or control voltages; or that the trouble is not in this unit at all; or that the output looks suspicious and further verifying tests need to be made.

Whatever the conclusion, the technician has discovered information that can be used to sub- stantiate or eliminate suspected units or pro- vide evidence for adding another. Tests of suspected unit outputs are continued until the single faulty unit is identified. At that point, the technician has narrowed down the trouble to a fraction of the total number of circuits and parts in the equipment. If at this time the proper procedure was carried out the search can be confined to the functional area isolated. NOTE: There are some equipments such as communications receivers, that cannot be easily divided into functional units. If this type of equipment is involved, steps 3 and 4 above, can be eliminated from the overall troubleshooting procedure.

LOCALIZING THE FAULTY CIRCUIT

After the faulty unit has been isolated, the next step is to identify the faulty circuit. The same narrowing- down procedures are used here as before. The unit is mentally subdivided into circuit groups by function, and valid technical reasoning is employed to select those that might probably contain the trouble. Using this pro- cedure the technician can find the faulty circuit without going through the unnecessary time- wasting chore of test-point to test-point check- ing from one end of the unit to the other. The technician works from the servicing block diagram of the unit. He then applies the information obtained from the preceding steps regarding the nature of the trouble. In narrow- ing down the trouble to a single functional group of circuits, the process used is called "bracket- ing." In this process brackets are placed, mentally or in pencil, around the area in which the trouble lies. Initially, a bracket is placed at the input(s) to the units that are known to be good and at the output(s) known to be bad. As each deduction is made and verified by a test, the input or output bracket is moved to the next point in the block diagram where the test was made. In this manner the closing brackets systematically narrow the fault to a single circuit.

In selecting a point on the servicing block diagram to which one of the brackets is to be

32

Chapter 2-MAINTENANCE

moved, the technician must consider two things: (1) the faulty characteristics of the improper output signal and (2) the types of signal paths contained in the unit. The waveshape of a signal contains characteristics— voltage, time, band- pass, noise content, frequency, etc.— that can be measured or observed. When these charac- teristics are in accordance with the designed standards, the signal is considered to be good. Bad signal characteristics that are improper can reveal clues that will help to identify a cir- cuit group whose function is to originate or control that portion of the waveshape. For ex- ample, the output of a unit is supposed to be a sawtooth waveform with six pulses, equally spaced on its slope. If the pulses are there but the slope is insufficient or improper, the saw- tooth generating and shaping circuits would be suspected. If the proper slope is there but there is insufficient number of pulses, the pulse generating or controlling circuit groups may contain the trouble.

Types of signal paths contained in the unit are the other items to be considered before moving a bracket. There are four general types: linear, switching, convergent/ divergent, and feedback. In a linear signal path, the signal is processed through circuits that are connected in series. When identification of the faulty circuit group is difficult or impossible, brackets can be moved to successively smaller half- points in the linear string. Signals from two or more circuit channels that meet at a common point or a signal that leaves a common point into two or more channels are examples of convergent/ divergent paths. Moving a bracket I to the common point (after making the appro- priate test) will separate the bad from the good signal paths. In the same manner, a test and bracket at the point where signal paths are connected by a switch will reveal the same in- formation. The remaining type (feedback loops) provides a means of bracketing a group of cir- cuits in the narrowing- down process.

There are no hard-and-fast step-by- step procedures in bracketing. But there are some realistic general rules.

1. Examine the characteristics of the faulty output to determine the circuit group function that either generates or controls the improper characteristic.

2. Study the servicing block diagram to determine the least number of bracket moves that will isolate the faulty circuit. Such moves will be dependent upon the types of signal paths

contained in the unit and the electronic func- tions of circuit groups that may be responsible for distortions contained in the unit's output.

3. Move only one bracket at a time after verifying the suitability of the signal by making a test.

4. When the test does not reveal sufficient information for a valid bracket move, make another educated guess.

5. The determination of which bracket to move is dependent upon circuit configuration within the unit and the smaller number of cir- cuits that will be enclosed.

The servicing block diagram can serve as the instrument for the completed bracketing process. In some cases it may be necessary to refer to a schematic diagram for bracketing or testing information. In any event there is suf- ficient diagram information available in the technical manual to support the bracketing procedure and preclude the wastefulness of unreliable circuit to circuit checking. This step is completed when the technician has isolated the trouble to a single circuit and veri- fied that the output of this circuit is the cause of the distortion read at the output of the unit.

FAILURE ANALYSIS

The troubleshooting procedure thus far has narrowed the trouble to a single circuit consist- ing of a tube (or transistor) and a few electronic components. If there is no output from the circuit, it may be permissible to resort to testing of tube pin numbers. However, such checks can be minimized if there is an output that can be examined for distortions that will reveal the circuit part that is most likely at fault. Quite often the waveform will identify the malfunction to be in the grid, cathode, plate, or screen portion of the circuit. Such a study should be made before any of the parts are checked.

When the faulty part has been identified, it should not be replaced until the technician can SUBSTANTIATE THAT IT IS CAUSING THE ACTUAL TROUBLE. A suspected open resistor, shorted capacitor, detuned coil, or weak tube may not be the reason or the only reason causing the faulty output of the circuit. If the technician replaces the part without an adequate technical reason, he may (when replacing the part) not have cured the trouble and he may yet cause further trouble. ANALYZE THE FAILURE BEFORE MA.KING THE REPAIR.

It can now be seen that the six- step trouble- shooting procedure is designed to isolate a

33

ELECTRONICS TECHNICIAN 3 & 2

trouble in an orderly manner. Success in using the procedure is dependent upon the technician's knowledge of electronics, the equipment under test, and his skill in using the technical manual and test equipment. The process is no more complicated than the ability to subdivide an equipment into progressively smaller functional areas, such as functional units into functional circuit groups, to a circuit, and finally a part or an adjustment within the circuit. It is the only logical way to trouble shoot any equipment, and it is more reliable and faster than any other method.

RECORDS AND REPORTS

Each activity engaged in the operation of electronic equipment is required to maintain cards for recording the results of inspections of equipments, and records of any tests, re- pairs, and field changes made. These cards provide a comprehensive record of the items concerned. They are kept up to date and avail- able for inspection at all times and are in-

tegrated into preventive maintenance programs such as the Current Ships Maintenance Proiect (CSMP).

All records and reports discussed in the following paragraphs are required except where the 3-M System has been implemented ANl5 where the type commander has indicated that they have been superseded by 3-M data pro- ducts or procedures.

ELECTRONIC EQUIPMENT MATERIAL HISTORY

The material history of electronic equip- ment consists of the Electronic Equipment History (Unit Location Card), NAVSHIPS 536-1 (8-66), (fig. 2-18) and the Electronic Equip- ment History Record Card, NAVSHIPS 536 (Rev 8-66) (fig. 2-19). One set of electronic equip- ment history cards is to be prepared and main- tained for each electronic equipment (or set) on board. The two cards (NAVSHIPS 536 and 536-1) are companion items. The initial or "top" card is the Electronic Equipment History

o o o o o o o o o o o o

AN/SPS-10 0

EQUIPMENT MODEL DESIGNATION

NAME OF CONTRAaOR

Dayatrom, Inc.

Radar Set

NAME OF EQUIPMENT

UNIT TYPE NO-

/\S-'^7UJSPS-/oB

C-JI3U/5PS-J0

CCJE-30AAP-I

J-^JQB/SPS-IO

m-J7iA/5PS-fO

m^nj^A/spsji

1234

EQUIP SERIAL NO

CONTRACT NO,

NObsr 75672

N.S. 93684

TECH MANUAL (NAVSHIPS) NO

NAME OF UNIT

'^^'^''^^•Tt-^'-a. CLi.a.f-yn.y(Jl^

Tf-dU^ j£f- G^^^

4

RcUa^ y?h^Lj£L^

DATE INSTALLED

10/10/63

(CttRKI

1

T M ON BOARD CARD NO

UNIT SERIAL NO

INSTALLING ACTIVITf

Phila, Naval Shltyard

///O

IZ.OI

"^97

/OO/

PF-8UA/5PS.I0

Rr-Z72A/SPS-IO

IZ.2.1

LOCATION (by name and compartmtnl So.)

CJ'C (OZ.-CO'-O-C')

/?aHi£<i/v7Xa-rM->ft<^ Tf't-t>->J.OZ-^Z.-l-Q)

/0 93

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ar^

//4t4

R<zi!</<, 7:a-*.^u.^»<^^ TF^^-wr (02-^2-/(3 )

tlEaRONIC EQUIPMENT HISTORY (UNIT LOCATION CARD) navships S3»-i is-»»i if.onti

Figure 2-18. -Electronic equipment history unit location card,

34

1.2

Chapter 2-MAINTENANCE

o|

ol

Oj

o o

0| Oi

oi oi

Oi

AM/SPS-10D

EQUIPMENT MOOEl DESIGNATION

Iz/l/CG

ymtuitin^ ^ A»-»t*-Cf

2/2/(^7

)fc

.-a^cr^

.yC-rlSUc-aXy^ •

Radar Set

NAME OF EQUIPMENT

123A

EQUIPMENT SERIAL NO

CORRECTIVE AaiON TAKEN

Q^ JJUr-j^ J^ /\Ap, ytZ^ GAycJMcbfJ^M/A •

m-n(,A izzi

JR^Je^^ ^ix4^ , )/-/09((^5jr)

yij, tkAjpCb \ ^-n.^ J(ji^<Ji-i</^ C^iaU^ C'pSi-->^jJ^ H^ <^

ClN-L3E>-)

CA-^ataf

UNIT TYPE NO

UNIT SERIAL NO

nr-ifz A

114-4-

1.2

Figure 2-19.— Electronic equipment history record card.

(Unit Location Card), NAVSHIPS 536-1, which is to be used as an inventory list. It provides space for tabulating all units of an equipment, together with serial numbers and installation locations. The Electronic Equipment History Record Card, NAVSHIPS 536, is used to record all failures and other work accomplished on an equipment. The NAVSHIPS 536 card has been arranged for chronological listing of all entries, regardless of the unit in which work was done. However, separate cards may be maintained for each unit, as deemed necessary by the individual activities.

All cards for a complete equipment are to accompany that equipment when it is removed from the ship or activity. In cases where an individual unit of an equipment is removed or substituted, a separate history record card, containing information pertinent to that unit, is to accompany the unit upon removal. If a chronological listing is used, it will be neces- sary to transcribe applicable data to a separate card.

NOTE: The two history record cards de- scribed and illustrated in figures 2-18 and 2-19 supersede the Electronic Equipment History Record Card, NAVSHIPS 536 (Rev. 9-48), and are to be used on all new equipment installa- tions. It is not mandatory that existing history records be revised to incorporate these new cards. Such revision may be accomplished at the option of the individual Electronics Material Officer.

The following instructions are to be followed in filling out the forms:

1. NAVSHIPS 536-1; This form is to be completed as soon after equipment installation as possible. The heading of the card should be typed, but entries on the body of the card may be typed or written in ink or indelible pencil as shown in figure 2-19. Individual col- umn entries should be made in accordance with the following guidelines.

Equipment Model Designation: All letters and numbers should be included to indicate the specific equipment. For instance, AN/SPS-IOD should not be entered SPS-10.

35

ELECTRONICS TECHNICIAN 3 & 2

Equipment Serial Number: This is the main equipment serial number and can be found on the nameplate bearing the overall equipment model designation. (In the case of the AN/SPS- lOD, it is located on the receiver-transmitter unit.) Do not use the unit serial. Where it is definitely established that an equipment does not bear a serial number, an asterisk (*) is to be entered in this space.

Technical Manual (NavShips) Number: Enter the applicable NAVSHIPS number in this space. For commercial manuals, enter the abbrevia- tion "Coml" and any other identifying numbers or data.

T. M. On Board: This space is to be checked when the final technical manual is received. If only the manuscript form of the manual is on board, the block should be left blank and a pencil notation inserted to indicate the status of the edition that has been received (whether manuscript is preliminary or advance). The pencil notation is then erased when the final edition is received.

Card No.: This space is to indicate the card serial. The numbering should follow, in con- secutive order, that ofthe Unit Location Card(s). If there is only one Unit Location Card, the number to be entered on the first History Record Card is "2"; all numbering of addi- tional cards filed for this equipment is to follow in sequence. If individual cards have been pre- pared, letter suffixes may be used to identify additional cards for each unit, e.g., 2A, b, etc. Name of Contractor: Enter the name of the contractor, in full, as given on the overall equip- ment nameplate or the technical manual.

Contract No.: This is to include all letters and numbers given on the equipment nameplate. Date Installed: This refers to the date the equipment was installed. If the installation was accomplished over an extended period of time, the completion date is to be entered.

Installing Activitv: This is the name of the activity or organization which actually installed the equipment.

Unit Type No.: This column is to list the official type (A-N) designations of all units that comprise the complete equipment. K commer- cial equipment, the manufacturer's designation is to be entered. All letters and numbers are to be included. -

Name of Unit: These are the official names of the units that make up the equipment.

Unit Serial No. : This column is to list the serial numbers of the units.

Location: Enter the unit locations in this column, using the name and compartment num- ber. If the unit is portable, indicate the space where it is normally stored.

2. NAVSHIPS 536: Since this form is used to list work performed on the equipment or fail- ures that occur, it is not necessary to prepare the card until the first problem is corrected. As shown in figure 2-18, the heading of the card should be typewritten, but entries on the body of the card may be typed or written in ink or indelible pencil. Individual column en- tries should be made in accordance with the following guidelines:

Model Designation,

Equipment

. ^ Name of

Equipment, and Equipment Serial No. : These entries should be identical to those made in the heading of the companion Unit Location Card.

Card No.: This space is to indicate the cardl

It

serial. The numbering is to follow, inconsecu- tive order, that of the Unit Location Card(s). If there is only one Unit Location Card, the number to be entered on the first History Rec- ord Card is "2"; all numbering of additional cards filed for this equipment is to follow in numerical sequence.

Failure Date: This is the date of a failure, the correction of a failure, or other work in- volving maintenance or repair.

Symptoms: This column is to be used to describe the symptoms exhibited by the equip- ment to indicate failure or faulty operation. The entry should be brief, but should describe the symptom in such a manner that it can be readily recognized by others.

Corrective Action Taken: This and the preceding column are most important. In this column enter the corrective measures taken to eliminate the fault described in the symptoms column. The entry can be brief, but should be as clear as possible. The clearer the informa- tion in this column, the more valuable it will be to the ship, the Navy Department, and the manufacturer. The cause of the problem is to be listed together with the parts replaced or adjustments made to correct the deficiency. Some activities may also wish to record in this column such information as the nam.e and rate of the person who actually accomplished the work, the man-hours consumed, and the sig- nature of the division officer. Such entries are optional.

Unit Type No.: This is to list the unit or units in which the corrective action was taken.

36

w

Chapter 2-MAINTENANCE

As shown in figure 2-19, the type number may be abbreviated.

Unit Serial No.: This is to include the serial numbers to the units involved.

Although time consuming, it is still possible to keep a complete and accurate material his- tory by having each man who performs a re- pair make the entry in the material history as soon as he finishes the job. To ensure that proper entries are being made, the Electronic Material Officer or leading ET should check them once a week for completeness and cor- rectness. Spot check should indicate whether or not entries are being omitted. Large ships often require repairs to be logged in a work book for checking by a supervisor, who then enters the appropriate information in the material his- tory. This procedure is successful where there is sufficient personnel; however, workbooks are not required by regulations. It is suggested that ETs on small ships log the repairs di- rectly into the material history. In many cases it has been found that the ETs fail to log re- pairs made by personnel other than ship's force, that is, those accomplished by tenders, ship- yards, and civilian technicians. These, too, must be recorded in the material history.

CURRENT SHIP'S MAINTENANCE PROJECT

The purpose of the current ship's mainte- nance project (CSMP) is to provide a current record of maintenance, modifications, and re- pairs to be scheduled and finally accomplished by ship's personnel or by repair activities afloat or ashore.

The CSMP consists of the following three cards:

NAVSHIPS 529-Repair Record Card (blue)

NAVSHIPS 530-Alteration Record Card

(pink)

NAVSHIPS 537 - Record of Field Changes (white)

As a repair is required or an alteration is authorized, the work is scheduled by filling out an applicable CSMP card and placing it so the top line of the card is in view alongside the proper history card, NAVSHIPS 536 (Rev 8-66). These CSMP cards are of distinctive color,

i which facilitates the indication of outstanding

i work when the history is examined.

: When the item of work has been completed,

entries are made in two places. One entry of the completion is made on the CSMP card.

and the other entry is made on the history card, NAVSHIPS 536 (Rev 8-66).

Upon completion of work, the Record of Field Changes, NAVSHIPS 537, remains with its NAVSHIPS 536 (Rev 8-66). However, NAV- SHIPS cards 529 and 530 are removed from their position adjacent to the history card and filed in a "completed work" section of the

CSMP.

The Repair Record Card, NAVSHIPS 529 (blue), and the Alteration Record Card, NAV- SHIPS 530 (pink) are identical as to block descriptions, therefore, the description of the entries apply to both cards. Their distinctive colors aid in distinguishing repair from altera- tion projects.

Repair Record Cards and Alteration Rec- ord Cards are retained for a period of 2 years, following which these cards may be destroyed at the discretion of the commanding officer. When ships are decommissioned or placed out of service during this period, the cards are re- tained onboard.

If the equipment is transferred, these cards are transferred with it.

Field changes scheduled and later made to any portion of an electronic equipment are re- corded on the Record of Field Changes, NAV- SHIPS 537, which is filed in the binder adja- cent to the history card for the equipment to which the change is applicable. Completion of filed change information is also entered on NAVSHIPS 536 (Rev 8-66).

This record is of paramount importance. Without modification, an equipment may be dangerously out of date and subject to numerous serious difficulties. Without a record of field changes it is difficult to determine what modi- fications, if any, have been made. The informa- tion recorded on these cards is essential for routine maintenance, for troubleshooting, and for ordering maintenance parts for the improved

equipment. . „. ,^

Figure 2-20 shows the Record of Field Changes Card, NAVSHIPS 537. The spaces for equipment model designation, serial number, date installed, and card number are filled in by typing or writing with ink or indelible pencil. The columns headed "No.," "Title of Field Changes," and "Authorityfor Change" are com- pleted in numerical order for all changes af- fecting a specific equipment. Field changes that affect certain equipments are made known in the Electronic Installation and Maintenance Book (EIMB). Enter applicable extracts from

37

ELECTRONICS TECHNICIAN 3 & 2

Figure 2-20.-Record of Field Changes (NAVSHIPS 537).

1.4

EIMB on the NAVSHIPS 537 card to indicate exactly its EIMB source and language The Electronic Information Bulletin (EIB) lists field changes and is also an authority for making such changes.

Do not use obsolete entries on NAVSHIPS 537. Approximately once a year, the Naval Ships System Command determines which EIBs become obsolete because their items are pub- lished elsewhere in permanent form (in EIMB and Instruction Book publications). For ex- ample, the initial 200 copies of EIB were named Repair Information Bulletin (RIB) and were canceled (as summarized in EIB 476) along with EIBs from serial numbers 1 through 380. Until further notice, serial num- bers above 600 shall be considered authoritative and directive in nature for announcing field changes that are active.

Many field changes are issued directly from the Naval Ships System Command to a Ship. Whatever its source, list the authority

for such changes in the column provided for it on NAVSHIPS 537.

EQUIPMENT FAILURE AND PERFORMANCE RECORDS

The Naval Ships System Command must re- ceive accurate reports from the fleet concern- ing equipment performance and failures, in order to evaluate its reliability and maintainability. Reports are also necessary to determine whether new equipments are meeting their design capa- bilities and operation requirements.

Reported failures are tabulated on IBM cards, and regular summaries are made to show at a glance the number and types of failures of any part of any equipment.

The importance of reporting failures and their causes cannot be too highly stressed, particularly if failures occur under actual op- erating conditions. The reports are to be filled m completely and in conformity with the in- structions accompanying the card. Many re- ports received by the Naval Ships System

38

Chapter 2-MAINTENANCE

Command are valueless because they do not give the essential information required by the form or because the information given is in- complete. When indicating the model or type of equipment, include all significant nomen- clature, letters, and digits.

Electronic Equipment Failure/ Replacement Report, DD-787

Failures to electronic equipment are re- ported according to NAVSHIPS Instruction 10550.73. The Electronics Failure Report form, DD-787 (fig. 2-21) and the Electronic Equipment Operational Time Log (discussedlater) are sub- mitted only upon failure of special equipments. The initial list of sepcified equipments is shown in the previously referenced NAVSHIPS instruc- tion 10550.73. Additions and deletions will appear in the EIB, which must be checked in each bi- weekly issue because listed additions will change your reporting requirements.

The DD-787 failure/replacement form is arranged so that all failure information relat-

ing to one equipment can be entered on the form. This should simplify the maintenance paperwork which resulted from earlier (obso- lete) requirements of listing only a single part on a single card. The DD-787 failure/ replace- ment form, combined with the Operational Time Log, NAVSHIPS 4855, provides the necessary data' for accurately showing: (1) mean-time- between failures, (2) mean- time-to- repair, (3) down-time, (4) availability, (5) failure rates, and (6) replacement (consumption) rates.

The report forms are packaged between man- ila tag covers andflaps, with 50 sets per package. The covers and flaps have printed codes and instructions for accurately completing the en- tries on the DD-787 form.

Electronic Equipment Operational Time Log, NAVSHIPS 4855

The Electronic Equipment Operational Time Log (fig. 2-22) serves a twofold purpose. First,

ELECTRONIC EQUIPMENT FAILURE/ REPLACEMEMT REPORT DD-787

REPORT BUSHIPS 10560-1

I. DESIGNATION OF SHIP 0« STATION

Z. REPAIKEO OH BEPO«TEO BY

UJ. "T^o&erf^^

er/

[Jus MAVY Z. n CONTRACTOR

ifl CIVIL SERVICE

iT-rPE OF nCPOBT tCMECK ONEI

REPAM OF

□ PRCVtKTlVE p-, HtW.ACE*»LE UNIT

WAINTENAKCE 9 LJ Oft PLU«-IN (POIKEe) ASStHSLT

□ PREVENTIVE P-, ._^_,

UAWTENANCE 1. 11 OTHER (NOT POHSCEl •— '

EQUIPMENT

4. TIME FAIL.OCCUHRED OR M*INT. B£3AN

~^

J

16_

y-^'/^

S. TIME FAIL. CLEABED OR MAINT COMPL

3

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-i=?o2^''

6. MOOEL TYPE DESIGNATION

7 EQUIP. SERIAL NO.

8 CONTRACTOR (NAVY COOe OR COmPLETE NAME)

<l.o/~

9. FIRST INOtCATtOH OF TROUBLE ICHtCK ONE)

5. n UWSTA8LE ORfRATlON

n?l INOPERATIVE __ „ »^

V» tQ NOISE OR VIBRATION

^.□0UT0FTOLERA«^.L0» , Q ^„„e„,„o y □ OUT or TOLERANCE. HWM ^ Q VISUAL OEPECT 4.|~| INTERMITTENT OPERATION j pi OTHER. EXPLAIN

REPLACEMENT DATA

10. OPERATIONAL CONDITION tCHECKONEt

1. M OUT OF SERVICE

0PERATIN6 AT zX~\ REOUCeO

CAPABILITf

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II. TIME METER REAPING

A. HIGH vOLTACE

B- FILAMENT /ELAPSED

12. REPAIR TIME

A/oA/if

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MAN-HOURS

13 LOWEST OESICNATED UNIT (Ulor SUa- ASSEW8LY (SA)

14. LOWEST DES. U/9A SERIAL NO

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15. REFERENCE

DESIGNATION

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16. FEDERAL STOCK NUMBER

It «FR.

OF REMOVED

ITEM

1. TYPE

OF

FAILURE

^53- >^ ^D

19. PRIMARY OR SECOND- ARY FAIL ?

!0. CAUSE

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22. REPL. AVAILABLE LOCALLY ?

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25. REPAIR TIME FACTORS

24. REMARKS

H0UR5 TEWTWS COOI

HOURS TENTHS

ICONTINUt OH REVERSE SiQE IF NECESSART)

Figure 2-21.-Electronic Equipment Failure/Replacement Report, DD-787.

39

15.2

ELECTRONICS TECHNICIAN 3 & 2

ELECTRONIC EQUIPMENT OPERATIONAL TtME LOG NAVSNIPS 4635 SUMir MOHTHLY fQg OC aPfLlCASLl COUiPMENT »MtTWEP « USE 0« KPT l »•'""''' ' '^'° J 2 OCSlGHATiOH QF SHIP OR sTaTIQW

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iLxz^y^s.

A!^S^iE_L%KHd^

OOIKIT WBITE BEI.OwmiSuillE- COHTlKuE Ql. k,£«5e sTOE

15.3

Figure 2-22. -Electronic Equipment Operational Time Log, NAVSHIPS 4855.

it is used to show accurate time-base data for figures-of-merit, which concern all failure- rate or replacement-rate calculations, or which concern other calculations that show reliability and maintainability factors. Second, it shows period of actual operation versus inoperative periods; such period values are known tech- nically as equipment population figures.

Without operation time or population figures that are reasonably accurate, any one or more figures of merit are not significant. There- fore, one realizes how the operation time is essential in evaluating other reports, especially the previously described DD-787.

The operational time log form is relatively simple to complete, especially when an equip-

ment is supplied with time meters. Only five or six entries need to be made on the first day of a month (depending upon the number of meters), and three more on the last day of the same month; a total of 8 or 9 block entries (on a single form) are to be completed per equipment per month.

Equipments without time meters require somewhat greater effort. The format for pack- aging and using these forms is explained in detail on the covers (similar to the DD-787).

Electronics Performance and Operational Report, NAVSHIPS 3878

The Naval Ships System Command must keep tab on new (and converted) equipments to eval- uate their usefulness. This is accomplished with the Electronic Performance and Operation Re- port, NAVSHIPS 3878, shown in figure 2-23.

It is not desired that reports be submitted on all equipments. Detailed instructions for the preparation and submission, and a listing of equipment requiring a report are contained in NAVSHIPS Instruction 9670-20E. When appli- cable, NAVSHIPS 3878 is submitted monthly to the Naval Ships Systems Command.

The NAVSHIPS 3878 reports are essential to keeping the Naval Ships System Command informed on equipment performance and op- eration. Because they provide first-hand in- formation on equipment under actual operating conditions and report the maximum ranges ob- tained, they are extremely valuable in evaluat- ing the electronics maintenance program, en- forcing manufacturers' guarantees, evaluating installation adequacy, improving equipment op- eration and safety, and improving equipment design.

The NAVSHIPS 3878 report contains a place for general remarks on the back of the form (not shown). Indicated here is any pertinent information not included elsewhere on the form such as detailed information on any unusual difficulty encountered in operation; exceptional maintenance required; and suggestions for im- provement in design, tests, and new applica- tions. The forwarding of suggested improve- ments is not to be construed as authority to modify the equipment in any way. Nor does the forwarding of this report eliminate the separate requirement for forwarding the Electronics Failure Report (DD 787).

40

Chapter 2-MAINTENANCE

ElECTRONIC PERFORMWtCt » OfERATIOHAL UfOBT

MViHIPS S»7» (««. %-») j^.i, .rltlmml *mtr «o fyf.." - *• rtr.,rdl^t '•«••' '•«""•■'

D

rt.ccT

m

USS RANGER (CVA-61) ;i"'

FROMi _ ' ^^ '

TO: CHIEF. BURCAU OF SHIPS {CODE Tf*t w«o MOOCL or lOWl'«*tN'»

AM-I365/URT Amplifier

I aintr ctniifOiTio*

UNCLASSIFIED

1 March 1966

1 FEB 68 |,. 28 FEB 66

IfMIM. MM«C»

383

rKLD CH*NCtJ TO OATC

ACCOM*! ISM to

None

••1 UXffWIVMO

None

;tsfo»,«ci rioo« fn » nowic* i»m»utiqm

M0o*5 oumno pitio© or •"• r^S*!..-

i;::- 180 '•'

O#<l*TI0M*t <WU.U*TIOIt

• l>£tMiai.( SlOlt. (MMl

35.83

Figure 2-23. -Electronic Performance and Operation Report, NAVSHIPS 3878.

41

ELECTRONICS TECHNtcIAN 3 & 2

SHIP ELECTRONICS INSTALLATION RECORD, NAVSHIPS 4110

The Ship Electronics Installation Record NAVSHIPS 4110, furnishes an up-to-date inven- tory of all electronic equipment aboard each ship to interested fleet and shore activities and is one of the records which will not be replaced by the 3-M system.

To be effective, the NavShips 4110 must be extremely accurate and must be submitted promptly. To indicate the importance and pur- pose of the document, the NavShips 4110's are specifically used:

(1) By the Naval Ships System Command for determining the equipments to be installed dur- ing overhauls and conversions, and the equip- ment to be procured in the future.

(2) By Naval Shipyards in overhaul planning.

(3) By the Electronic Supply Office to de- termine repair parts allowances.

(4) To prepare Coordinated Shipboard Al- lowance Lists (COSAL).

Instructions for preparing, revising, and sub- mitting NAVSHIPS 4110 are contained in NAV- SHIPS 900, 135D.

ELECTRONIC MATERIAL IDENTIFICATION

Numbers currently used by the Navy to Identify and catalog electronic repair parts are Federal Stock Numbers (FSN), These are the numbers which should be used on all supply and inventory documents.

The FSN used throughout the Department of Defense utilizes a 4-3-4 digit pattern prefixed by a numeric-alphabetical designator called a dual cognizance symbol (fig. 2-24). The numeric-alpha combination identifies the gen-

eral category of the material, the funding, the Navy Inventory Control Point having cognizance or the Navy Retail Office having administrative responsibilities for the items under the mana- gership of a Defense Supply Center.

Following the dual cognizance symbol is a four-digit number which indicates the Federal Supply Class. The first two digits represent the Federal Supply Group. In the example shown in figure 2-24, the "59" specifies that the item IS an Electrical/Electronic Equipment Compo- nent. The second two digits, "20" together with the number "59" show the Federal Supply Class in which fuses and lightning arrestors have been classified. The last seven digits- the 3-4 part of the pattern-are the specific item identifier. They are called Federal Item Identification Numbers (FHNs) and are seri- ally assigned. The same FHN is never used to describe more than one line item, and once assigned, that number is never reassigned, even though the item identified by the num- ber may have been dropped from the supply system.

Where FSNs are not available, other num- bers must be used to identify the repair parts. Such other numbers may be reference num- bers or manufacturers' part numbers. Each company or concern which manufacturers ma- terial for Government use is assigned a five- digit "manufacturer's code". The use of a reference number, part number, or manufac- turer's code is important in the identification of a part when the FSN is unavailable.

U. S. NAVY ELECTRONIC SUPPLY OFFICE

The U. S. Navy Electronic Supply Office (ESO) is located at Great Lakes, Illinois,

Stores Account Code Cognizance Symbol —

Federol Supply Cloisification Group Federal Supply Classification Class

Federal Item Identification Number (FUN)-

N 5920-284-5707

Figure 2-24.-Breakdown of typical Federal Stock Number.

42

107.13

Chapter 2-MAINTENANCE

where inventory control is exercised over as- signed electronic material. ESO has been des- ignated by the Secretary of the Navy to serve as the inventory control point for Navy Ships System Command electronic repair parts (less nuclear items) required in the maintenance, upkeep, and overhaul of equipments in ships and at shore stations, other than those for which control is specifically retained by the System Command.

A part of ESQ'S primary mission of sup- plying activities in the electronics distribu- tion system with repair parts is to prepare Coordinated Shipboard Allowance Lists (COSAL) for ships and Electronic Repair Parts Allow- ance Lists (ERPAL) for shore stations, de- velop and maintain stock numbered parts lists (referred to as SNITs or Stock Number Iden- tification Tables and APLs or Allowance Parts Lists) for individual equipments, and partici- pate in the initial provisioning of parts for new electronic equipments.

The U. S. Navy Electronics Supply Office stocks no material. It controls and directs the flow of assigned electronic material through the electronics supply segment of the Navy Supply System,

MAINTENANCE OF STOCK LEVELS

The necessity for a consumer activity to maintain sufficient stocks to meet its require- ments is obvious. Less obvious, but also im- portant, is the necessity to avoid overstock- ing. Overstocking not only increases the dollar value of an activity's inventory and occupies storage space unnecessarily, but stocks which may be needed elsewhere are immo- bilized.

Certain parts may require replacement so often that there may be a tendency to consider them as a part of shop stores. In such a case, an increase in the quality of manufac- ture, an improvement in design, or obsoles- ence may leave the shop store with a 6 -year instead of a 90- day supply. For this reason alone it is desirable to keep shop stores to a minimum.

REQUISITIONS

In order to have on hand replacements for parts which fail, activities operating electronic equipments must make their requirements known to the supply system. This is done by means

of requisitions forwarded to the appropriate supporting supply activity. The supply officer is responsible for requisitioning materials, however, he must be told what materials and quantities are needed.

After a requirement is identified it must be transmitted to the supply department in some acceptable form. Ultimately, documentation must be prepared and processed which ac- complishes the recording and accountability requirement.

Ashore and on ships with data processing equipment, which include most aircraft car- riers, the DD Form 1348 is used as the re- quest' and issue document. An example of a properly prepared DD Form 1348 is shown in figure 2-25. The shaded areas on the form indicate which information is furnished by the customer, with the balance of the information being completed by supply department person- nel.

On ships operating under manual supply procedures, which include the majority of all ships, the NAVSANDA Form 1250 is used as the request and issue document. An example of a properly prepared NAVSANDA Form 1250 is shown in figure 2-26. The shaded portion of this document indicates which information is furnished by the customer.

EQUIPAGE CUSTODY

Equipage is the term used to designate nonconsumable material. This type of ma- terial has greater value than consumable sup- plies and more functional importance, such as signal generators, multimeters, and oscillo- scopes.

A custody signature on Equipage Stock Cards and Custody Record, NAVSANDA Form 306 (fig. 2-27) is mandatory for equipage under Naval Ships System Command cognizance, as listed in NAVSUP Manual, Volume III; and equipage items which the commanding officer determines should have a custody signature.

A copy of the Equipage Stock Car* |pd Custody Record must be furnished to the «#- partment head at the time he signs the original custody card. The duplicate copy becomes the department head's record of equipage requiring custody signature for which he is responsible. As equipage is received or expended, appro- priate entries are made on all equipage rec- ords.

43

ELECTRONICS TECHNICIAN 3 & 2

°i.T,l„i.,.|;| sloe. NuMae. ^ „V«, ""•"''ITV »■<■■•■;■; .■■■13.. i | „.i.r: ( ^»_^,.,.,...

■V — I — r-

04660^08JOOJ(9

/fE

65 I 66 i er I 68 I 69 70 Tl 72 73 I 74 T'

DOC. IDENT,

TT — ' —

f?^„?l0UflN

!'..■ ■ I, I

PEQUPSITION IS FROk,

^-70

STOCK Nl u t.

~T 1 — T — Hrn 1-

aDOiTiois,A

""' I TT-i r

3nOJ5^<^U/p

RE MA R KS 1

■'■'■''■■

/5a/

Z.QOIIT0

Bk

QUANTITY ^

/

^.20

1?.**i^.

; ! s

;:.... ' ' '•'^■'''-"'^''''''''^"a'a;^""r;;;^'r5m^M3gs^

Figure 2-25. -DD Form 1348.

43.24

A Prom (Wck Cint«r CodtJ

[Z. ROD

B DEPT NO

^8

3 <

ISSUE TURN-IN

0 D

STOCK NUMBER

<^3Ho

>lA^Mt

ADDT'L

I I r

J__L

D D

SIM NON-SIM

D 0

30/ ^S

M INVENTORY

REFERENCE SYMBOL OR NOUN

__^ CID/APL/AEL/AN

TTTTI I I — I — I — I —

...1 . „■ ■ \ \ \ r\

d EQUIPMENT DATA ISUP'TEDI

J L

T_ I . I I — r

-00 I I JO

D D

r. J^^l

EA

DAY - MO. - YR.

1 I r'^~

. CONTROL CODE

U. APPROVED BY

S/R ISSUE S/R REO'N 0/s

G REQUISITION NO

0 SHIP HULL NO

1

"T-xn-T

J l_L

uic

~~\ I r

"I I I r

I i I L

20

T REMARKS

J 1 I I

P EXT PRICE

IV RECEIVED BY

IVEO BY y^ J

9 ■^j>--?n..^^^^

Figure 2-26.-NAVSANDA Form 1250.

17.84

When the department head issues the eq- uipage, he should have that person sign a sub- custody receipt; however, this does not relieve the department head of the responsibility for the equipage.

SURVEY REPORTS

A survey is the procedure required by U.S. Navy Regulations when naval property must be condemned as a result of damage,

44

Chapter 2-MAINTENANCE

Figure 2-27. -Equipage Stock Card and Custody Record, NAVSANDA Form 306.

7.3

obsolescence, or deterioration, or is acknowl- edged as nonexistent as a result of loss, theft, or total destruction. A survey is made on Survey Request, Report and Expenditure, NAVSANDA Form 154.

Formal surveys (fig. 2-28) are made by a commissioned officer or a survey board ap- pointed by the commanding officer. A formal survey is required at all times when it ap- pears that responsibility for lost or damaged material may be placed on a person or persons in the naval service. Also, formal surveys are required for certain classes of material or articles designated by the bureau or office concerned. In the absence of instructions from higher authority, the commanding officer de- termines whether a formal or an informal survey is required.

Informal surveys will be made by the head of the department having custody of the ma- terial to be surveyed. A survey will be made

when a material condition becomes known or when instructions by higher authority direct a survey.

ADDITIONAL REPORTS

Type commanders and other authorities may require reports in addition to those required by the Navy Department. Instructions concerning such reports may be promulgated via letter, message, or other official means. The Elec- tronics Technician, therefore, must examine all official correspondence regarding electronics forwarded to his activity in order to keep abreast of current instructions.

ELECTRONIC SAFETY PRECAUTIONS

There is great diversity in the dangers in- herent in the technician's work. These dangers range from those encountered while working

45

ELECTRONICS TECHNICIAN 3 & 2

«i«yEY REQUEST, tEMRT AND EXHNDITURE

(52198) USS Jones Ingram (DD-938)

0«ICINAIC«(S,5„o,„,, „^ ,,„„

1 Aup. 1967 haiqff'iPifin?;,';

REQUEST FOR SURVEY

.C. Sword. LTJr,. ■ IISMB, f^.

peratlongOff .

STOCI HO. IND OfltllfTIOH

Oscilloscope 0S-8E-U 2F 6625-649-9248

■ lAlON FOR SutVfY

Damaged beyond economical repair

• CCOUNf IN WHICH CAHItS (AM. N5A, .«. o, non.lo,,,)

Nonstores

UMIT flict

$120

$120

TTP[ OF SUIVIT [yl fO«M*l

I I INrOtMA

SUIIIT 10 IE use If

ACTION »Y COMMANDING OFFICER OR DELEGATE

OTMtB DATA (Soi/zc, (jol* oF r»<«,pf, .hj

NSC, Norfolk 10/25/67

LTJG. R.R. Toi.^r-

I. IT.ir,. H.R, Rar-ncf,

1. LTJG. S.M. Lindquist

JIGNATum (C, O. w dthgottl

R.E. Spallc

(OAFF) 1 Aug. 1 967

pallone, CDR., USN

SURVEY REPORT AND RECOMMENDATION

Condition: Damaged beyond economical repair

Cause: Dropped on deck while being moved during heavy seas; considered unavoidable

Responsibility: None

■ ICOMMINDATIONS

BIJ,

□ IRANI TO •-

TRANSPIR

>70

□ TlANtril TO MAT'l

l«A»(S| SURVfYfO IN ACCOIDANM WIIN NAVY REGUlATiONS »r; |S,b»oi„,.{,|1

(f.i ttpo" ton] CON*. COM |i ) I |_

ITfA^S) SURVfYfO IN ACCOHOANCt WITH NA'

LTJG. R.B. Lc^er '

liJ ArneviB []] BitAPnoviD

Figure 2-28.-Survey Request, Report and Expenditures, NAVSANDA Form 154.

46

7.6

Chapter 2-MAINTENANCE

aloft to those of nuclear radiation. The tech- nician is also exposed to the dangers of working with high voltage, RF radiation, volatile and com- bustible materials, and with power tools, etc. The list is almost endless. It must be stressed, however, that these dangers are potential dangers; dangers that can be eliminated, or at least minimized, if the proper safety precautions are observed.

Safety precautions are not stagnant; rather, they are continuously changing. A complete list of safety precautions for today may be inadequate for tomorrow. Advances in technology are often accompanied by new dangers, necessitating new safety precautions. In addition, continuing re- search in the area of safety periodically brings to light heretofore hidden dangers.

Only by the following actions can you ensure that you are aware of all of the dangers which may be encountered in your work and that you know all of the necessary safety precautions that must be observed:

a. Ensure that all the publications pertaining to safety are aboard. (A complete list of these publications is at the end of this discussion.)

b. Maintain these publications in a current status by making the corrections and inserting the changes as they are received.

c. See that your name is on the routing list for all periodicals that may contain articles on safety; such as the EIB or the Navy Ship System Command Technical News.

SOURCES OF INFORMATION

Unfortunately, all of the precautions neces- sary to ensure the safety of the technician can- not be found in any one publication. They all exist, however, in the many publications, peri- odicals, and directives of the various offices and bureaus of the Navy Department. It is the purpose of this discussion to provide a list of authoritative sources of safety information. OPNAV Notice 5100 of 4 November 1964 states that the Chief of Naval Operations will ' periodically publish an index of publications, pamphlets, periodicals, and directives, issued by the bureaus, system commands, and offices of the Navy Department, which contain safety

precautions applicable to the operating forces. The index is issued as a series of OPNAV Notices under the 5100 subject classification number, and provides an up-to-date list of all published ma- terial pertaining to safety precautions. Every Electronics Technician should check this list and ensure that all publications that are ap- plicable to his division are readily available to himself and to others within the division. The following list of publications was taken from the OPNAV Notice stated above, and in- cludes those of most importance to the tech-

nician:

Title

Naval Ships Tech- nical Manual Chap 9670, Sec V

Electronic Installation and Maintenance Book (EIMB) General Handbook

EIMB Installation Standards

Electronics Informa- tion Bulletin (EIB)

Instruction

Instruction

Various Equipment Technical Manuals

Standard First Aid Training Course

Department of the Navy Safety Pre- cautions for Shore Activities

Type Commanders' or Commanding Officers' Directives

Number

NavShips 250,000

NavShips 0967-000- 0110

NavShips 0967-000- 0130

NavShips 900,022A

NavShips 6260.5 BuMed 6200.5

NavPers 10081-B NavSo P-2455

47

CHAPTER 3

USE OF SPECIAL TEST EQUIPMENT

The purpose of this chapter is to better acquaint the technician with the purpose and practical use of special test equipment. The test equipment discussed is by no means all that will be encountered; however, it is rep- resentative of special types of test equipment that you will find aboard most ships and at shore stations.

RADIO INTERFERENCE MEASURING SETAN/PRM-IA

Radio Test Set AN/PRM-IA (fig. 3-1) can be used for radio interference surveys to de- termine the source of radiated or conducted interference from any source within its fre- quency range. Such interference may be gen- erated by gasoline engine generators, motors or electronic equipment. Field intensity meas- urement surveys may be made with Radio Test Set AN/PRM-IA for adjusting directive an- tennas or for exploring radiation patterns, where the field intensity may vary over a wide range of values. The equipment may also be used as a sensitive radio frequency microvoltmeter. The test set is portable and is suitable for operation aboard naval ships, at shore stations, in the field, in aircraft, and in military ve- hicles.

TYPES OF RADIO INTERFERENCE

Radio interference, sometimes called "noise", disrupts the utility of radio fre- quency receivers. Interference includes many forms of disturbances and may be roughly classified as continuous and discontinuous.

Continuous disturbances include random in- terference such as thermal agitation. Atmos- pheric interference, or static, originating in lightning discharges in local storms and in more distant tropical storms, resembles ran-

dom interference in that the impulses are fre- quent and overlap, with sharp peaks exceeding the average level. If interference impulses fol- low each other rapidly and are not clearly distinguishable, then the interference is random.

Discontinuous interference is made up of sharp pulses, the frequency determining the character of the interference. If the pulses are relatively infrequent and clearly separated, the interference is termed impulsive. Impulsive in- terference may be generated by an internal combustion engine ignition system, power line discharges, electrical switching operations, electronic equipment, and by other electrical and electromechanical devices.

Because of the wide frequency range covered by continuous and discontinuous interference, the magnitude of the interference will depend upon the bandwidth of the measuring equipment. The bandwidth characteristics of the AN/PRM-IA are taken into consideration and are utilized in obtaining average, quasi-peak, and peak values of interference. Shipboard electronic interfer- ence is described in the Electronic Installation and Maintenance Book, NavShips 0967-000-0150,

FIELD INTENSITY MEASUREMENTS

Field intensity is the value of the electric field at a given point and is measured in terms of volts-per-meter. One volt-per- meter is equivalent to a potential of one volt induced in a vertical rod antenna having an electrical length of one meter.

There are two principal methods of making field intensity measurements. One method is the substitution method, in which a loop antenna is connected to a receiver, and metering cir- cuits give an indication of the receiver output. The receiver is tuned to the desired signal. The loop is rotated to give maximum signal, and the relative value of the received signal is

48

Chapter 3- USE OF SPECIAL TEST EQUIPMENT

®

RF PROBE MX-980/PRM-I

Antenna AT-2M/PRM-I

	:-'< ^	^	®
Adopter		N^	Adopter
Connector		^	Connector
UG-I05/U			UG-I04/U
d)		CG-444/U (20' 0") -	\

®

Rodio interferenve -Field Intensity Meter 1M-37A/PRM-I

vly Transit

VCV Accessory Cose

CADV-62480 (6' 0*)

LEGEND

Cose CY-749A/PRM-I

Headphones

Novy Type 49507A

CY-750/PRM-I

162.2

Figure 3-1. -Radio Test Set AN/PRM-IA, Connection Diagram.

49

ELECTRONICS TECHNICIAN 3 & 2

recorded. The loop is then rotated to give mini- mum received signal, and a signal generator is inserted in series with the loop. The signal gen- erator is tuned to the received frequency and its output adjusted to obtain the same receiver reading of signal input as was obtained with maximum loop signal. The field intensity in microvolts-per-meter is computed from V

the formula E

where V is the value

H{eff),

of the substitute signal in microvolts and H(eff) is the effective height of the antenna. To ob- tain the effective height of the antenna use the following formula;

H(eff) = 1.351 ANF x 10

8

Where

A = area of 1 turn of loop winding in square

inches N = number of turns F = frequency in kilocycles, and H(eff), is

in meters.

The second method of field intensity meas- urements employed in the AN/PRM-lA uses a specially designed sensitive receiver with built- in attenuators and a calibrated voltage source. The Radio Interference- Field Intensity Meter IM-37A/PRM-1 is tuned to the desired fre- quency and the calibrated voltage is applied to the r-f input. The gain of the i-f section is then adjusted to give a standard value of calibrator signal input. The calibrating voltage is turned off and the antenna is connected to the RI-FI Meter input.

The attenuators (discussed later) are ad- justed for a meter indication at the upper half of the indicating meter dial, and the meter read- ing thus obtained, multiplied by the attenuator setting and the effective height of the antenna used, is the field intensity in microvolts-per- meter of the received signal. This method is advantageous in that the accuracy is independent of signal frequency, and depends primarily upon the attenuator and the linearity of the RI-FI meter circuits.

GENERAL THEORY OF OPERATION

Radio Test Set AN/PRM-IA is basically a meter intended for intensity measurements of all types of radio frequency energy in the low and medium radio frequency spectrum

between the limits of 150 kilocycles and 25 megacycles.

The Radio Interference- Field Intensity Meter IM-37A/PRM-1 (fig. 3-1) includes a sensitive receiver and a vacuum-tube voltmeter (VTVM) section. It also contains internal means for standardizing the receiver gain, thus permitting direct readings in indicated microvolts or microvolts-per-meter.

By special input circuit design, provision hasi been made for use of the equipment in the follow- ing ways:

1. A field intensity measuring equipment op- erating from a vertical antenna of convenient size.

2. A field intensity measuring equipment op- erating from a loop antenna with directional properties.

3. A field intensity measuring equipment op- erating from a small probe responsive to an induction field.

4. A two-terminal voltmeter making both: symmetrical and asymmetrical measurements with respect to ground.

A set of eight charts contain simplified op- erating instructions and a family of calibration curves that are plotted for each individual Radio Interference- Field Intensity Meter IM-37A/ PRM-1.

R-F INPUT DEVICES

Input devices for Radio Test Set AN/ PRM-lA (fig. 3-1), include a rod antenna, a loop antenna, a loop probe, an r-f probe, and impedance match ing networks.

Rod Antenna

Antenna AT-213/PRM-1 is a telescopic ver tical rod antenna with an effective length of ap proximately one-half meter and a physical length of 41 inches. The voltage range of the rod An- tenna AT-213/ PRM-1 is from two microvolts- per-meter to two volts-per-meter. The rod antenna is a capacitive pickup device, and meas urements made with this antenna are affected by conductivity of the ground, nearby metal structures, and the body effect of the operator. For optimum accuracy when using the rod aa tenna, comparison measurements using the loop antenna and the rod antenna must be made at the frequency in use. The correction factor so obtained is then applied to the rod antenna meter reading.

50

Chapter 3-USE OF SPECIAL TEST EQUIPMENT

Loop Antenna

Antenna AT-212/PRM-1 is a shielded loop with rectangular shape and an equivalent diam- eter of 8 1/4 inches. The loop is a solenoid winding consisting of 2 turns of 13 strand #36 wire, with a voltage range from 10 microvolts- per-meter to 100,000 microvolts-per- meter. The loop antenna may be used as a hand-held probe connected to the end of the 20-foot cable CG-444/U used with the probe antennas.

Loop Probe

The hand-held probe Antenna AT-211/PRM-1 is connected to the LOOP receptacle on the Radio Test Set by means of the 20-foot cable CG-444/U. The loop is a universal winding 1/2" effective diameter, consisting of 13 turns of 15/44 wire. It is enclosed in a phenolic case and can be rotated on its base to utilize the directional characteristics of the loop. The voltage range of the loop probe antenna is from approximately 1,000 microvolts-per-meter to approximately 10 volts-per-meter.

R-F Probe

The r-f Probe MX-980/PRM-1 permits use of the RI-FI meter as a two-terminal volt-

meter for measurement of conducted inter- ference on a line. The unit is connected be- tween one side of a line and ground or two lines, balanced or unbalanced to ground. In use, short insulated jumpers are connected to the probe input and the free ends of the jumper are connected to one side of the line and to ground.

Impedance Matching Networks

The three impedance matching networks, CU-195/PRM-1, CU-196/PRM-1, andCU-197/ PRM-1 are physically identical except for cir- cuit impedance. They are connected to the ANT receptacle where they present a capacitive reactance equivalent to that of the rod antenna. The 50-ohm unit, CU-197/PRM-1, and the 20- ohm unit, CU-196/PRM-1, are intended for use where it is desirable to terminate a transmis- sion line, an antenna, or other circuits in these resistance values at the input to the RI-FI Meter. The unterminated unit, CU-195/PRM-1, is intended for use with signal generators or other devices whose output is not meant to be terminated in a low resistance.

CONTROL CIRCUITRY

The signal channel, as is evident in the simplified Block Diagram (fig. 3-2), closely

ANTENNAS	DESCRIPTION
flT2-3/PRM-l	41 "ROD
AT-2I2/PRM-I	LOOP
AT-2II/PRM- 1	LOOP PROBE
MX-980-PRM-I	LINE PROBE

IMPEDANCE MATCHING NETWORK

CU-I95/PRM-I

GENERAL PURPOSE

CU-I96/PRM-I

20-ohms

CU-I97/PRM-I

50-ohms

RF- STAGE

MIXER

FOUR IF STAGES

DETECTOR

TWO AUDIO STAGES

CALIBRATOR

LOCAI OSr

BFO

METER

VTVM STAGE

CIRC

UITS

11

162,3

Figure 3-2.— Radio Test Set AN/ PRM-1 A, Simplified Block Diagram.

51

ELECTRONICS TECHNICIAN 3 & 2

resembles a superheterodyne receiver in its r-f, i-f, and a-f portions, but differs from most superheterodyne receivers in its provision for attenuation and measurement of detector output.

R-F and I-F Attenuator

The built-in step attenuator provides the following step ratios: 1, 10, 100, 1,000, and 10,000. Provision is made to obtain these ratios by discrete combination of attenuation in the antenna circuit and the first i-f stage.

R-F Stages

The r-f signal or interference (as picked up by the antenna or probe) is delivered to the LOOP or ANTENNA receptacle (fig. 3-3) at the r-f input. The r-f signal is amplified in the r-f stage (fig. 3-2), and mixed with the local oscillator frequency in the mixer stage, to produce the intermediate frequency. The use of two intermediate frequencies (455 KC and 1600 KC) is used to provide continuous

LOOP

INPUT RECEPTACLE

INDICATING METER

BFO

ENERGIZES BFO CIRCUIT

FREQUENCY BAND INDICATOR

BAND SELECTS FREQUENCY BAND

AUDIO ADJUSTS VOLUME LEVEL

PEAK

CONTROL SLIDE BACK VOLTAGE

CAL

ADJUSTS FOR STANDARD METER INDICATION

POWER SWITCH SCOPE _

FOR OSCILLOSCOPE CONNECTION

FUNCTION SWITCH

AUDIO OUTPUT FOR HEADPHONES

ANTENNA

INPUT RECEPTACLE

FOR CONNECTION TO EXTERNAL GROUND

INPUT CONTROL SELECTS INPUT TO RF SECTION

TUNE TUNES RF SECTION

ATTENUATOR CONTROL ATTENUATES RECEIVED SIGNAL

. METER

CONNECTS METER FOR USE IN VTVM CIRCUIT OR FOR MEASURING A AND B VOLT- AGES

B AOJ ADJUSTS PLATE VOLTAGE

- A ADJ ADJUSTS FILAMENT VOLTAGE

POWER FOR CONNECTION TO POWER SUPPLY PP-472/PRM-I

EXT METER FOR CONNECTION TO AMMETER ME-33/U

Figure 3-3. -Radio Interference- Field Intensity Meter IM-37A/PRM-1, Panel Controls and Receptacles.

162.4

52

i

Chapter 3-USE OF SPECIAL TEST EQUIPMENT

frequency coverage from 150 KC to 25 MC. On all bands except Band 7, the local oscilla- tor frequency is above the input signal fre- quency. See table 3-1.

I-F Amplifier Assembly

The i-f amplifier assembly consists of four i-f stages and a BFO (beat frequency oscilla- tor). The first two i-f stages are deciding factors in determining the operational charac- teristics of the VTVM at the receiver output. In this connection, operating potentials of the two stages are arranged so as to obtain log- arithmic deflection on a two-decade meter. All i-f stages have separate tuned circuits for each i-f frequency, the appropriate cir- cuits being selected by the Band Selector Switch (fig, 3-3).

Two intermediate frequencies are used in the seven frequency bands as listed in table 3-1. The table also shows how the local os- cillator is tuned to produce the i-f (difference) signal.

Table 3-1. -Listing of I-F Frequencies and Local Oscillator Frequency

Band I-F Frequency Local Oscillator

Band 1

Band 2

Band 3

Band 4

Band 5

Band 6

Band 7

455 KC

1600 KC

455 KC

455 KC

1600 KC

1600 KC

1600 KC

Frequency

Above signal frequency

Above signal frequency

Above signal frequency

Above signal frequency

Above signal frequency

Above signal frequency

Below signal frequency

The third i-f stage (not shown) is similar to the preceding two stages with the exception of the addition of a gain control. The fourth

i-f stage (not shown) is a power driver stage for increasing the dynamic range, utilizing a pentode power amplifier tube.

The beat frequency oscillator is used for aural reception of CW signals. The audio sig- nal is produced by heterodyning the i-f signal frequency and the BFO frequency. The BFO switch (fig. 3-3) must be placed in the BFO position, to apply filament voltage to the BFO. When the switch is in this position, the indi- cating meter is disabled and no readings can be made. The BFO is not to be used for zero beating the i-f signal.

Detector Stage

The detector stage demodulates the i-f sig- nal utilizing a linear diode detector circuit. The diode output branches into two circuits - to the first audio stage and to the AGC and VTVM circuits.

VTVM STAGE

Two pentodes are employed in the VTVM stage, which is a circuit adaptation of a bal- anced VTVM circuit. The d-c voltage to be measured is applied to the first stage and upsets the balance of the stage, causing the indicating meter to deflect upscale and indi- cate the magnitude of the unbalance.

The use of this balanced VTVM circuit counteracts the effect of supply variation since supply variations will affect both tubes equally. Balance is indicated by a zero reading of the meter when no signal input is present.

Provision is made in the VTVM circuit for connecting an external meter in series with the panel-mounted meter.

WEIGHTING CIRCUITS

The term "weighting" as applied to the AN/PRM-IA specifically refers to the time constant introduced in the detector and AGC circuit. This "weighting" effectively deter- mines the time versus voltage characteristics of the indication obtained.

The weighting circuits are selected by the function switch and serve to properly weight the voltage supplied to the indicating meter for the three types of measurements performed by the equipment. The weighting circuits also determine the AGC time constant.

53

ELECTRONICS TECHNICIAN 3 & 2

Field Intensity Circuit

The AGC and VTVM circuits see a voltage source which charges slowly and discharges slowly so that the meter indication continuously shows an average of the input signal over 600 milliseconds. This is accomplished by the time constant of an RC circuit.

The meter reading for field intensity is proportional to the field intensity of radiated signals, or proportional to the averaged value of r-f interference. The reading will be in- dependent of modulation in the case of modu- lated CW signals due to a filter preceding the Weighting Circuit.

The Quasi- Peak Circuit

In the quasi-peak function, the time con- stants of the detector weighting circuits are approximately one millisecond charge and 600 milliseconds discharge. This is arranged by charging a capacitor through the relatively low resistance of a diode and discharging the capacitor slowly, through a resistive load. The meter indication then is near the peak value of an interfering signal, including pulse sig- nals with PRF as low as 300 per second.

The Peak Circuit

In the peak function, the circuit is similar in some respects to the field intensity cir- cuit. The VTVM and AGC circuits are the same, but an additional bias circuit has been added to enable the measurement of peak signal values. The peak value measured is the "peak" as seen by the second detector and not the true peak of the signal at the antenna input. The PEAK function of the function switch acts to apply a d-c voltage in parallel with the signal input. The circuit is similar to an adjustable delayed AGC system, since the d-c voltage is also applied to the detector. The d-c voltage is manually adjusted to the threshold of diode rectification. This measurement technique is similar to that employed in the "slide-back" voltmeter.

POWER SUPPLY

The Power Supply PP-472B/PRM-1, (fig, 3-1) is designed for operation from any a-c power source within the limits of 105-125 and 210-250 volts, and at any frequency between

50 and 1600 cycles per second. It provides a regulated positive 75 volts output for B+ and a 1.1 volts for filament power. When a 230 volt power source is used, the line voltage is reduced to 115 volts by action of an autotransformer. Radio Test Set AN/PRM-1 uses self-contained plate and filament voltag© batteries for limited periods of operation in the field. At all times, including periods when the a-c power supply is used, two 4.5 volt and two 1.5 volt bias voltage batteries arei required.

RADIO INTERFERENCE CONSIDERATIONS

An open, flat terrain is preferred for mak- ing field intensity measurements to avoid the: possibility of absorption by dense growths of trees or steep ridges. Also, the face of a' nearby cliff may act as a reflector and pro- duce local variations in the intensity of the interference measured.

To isolate the radiated field from the in- duction field of a source of interference, make radio interference measurements of a radiating source at distances greater than twice the wavelength of the radiated signal. As the amplitude of the induction field energy varies inversely as the square of the distance from the source, the effects of the induction field are negligible at distances greater than two wavelengths.

Interference measurements made near power lines are subject to inaccurate results because of possible reradiation from the power lines. Every attempt should be made to avoid locat- ing the equipment near closed loops present in iron frame buildings and topside structures aboard ship. If possible, avoid locating in the vicinity of underground pipes, trolley cables, or rail lines.

When the equipment is installed aboard ship or in a vehicle, it should be remembered that the metal body or frame tends to distort the pickup pattern of the dipole antenna. In addi- tion, closed loops formed by wiring or struc- tural members will affect the field pattern. In some cases, these errors can be determined with the equipment mounted in a designated location. Correction factors so obtained may then be applied to compensate for pickup pat- tern distortion.

When a variety of equipment, including radio receivers, is employed at any one site, a check

I

54

Chapter 3-USE OF SPECIAL TEST EQUIPMENT

for interaction between equipments should be conducted.

The ideal site for making interference sur- veys is an open, flat terrain at a considerable distance (1000 ft or more) from buildings, elec- tric lines, fences, and other wave obstructing devices. Ideal sites are rare in the more populated sections of the country. Therefore, it is good practice to check a proposed loca- tion by making signal measurements of the desired signal at several points in the vicinity. If the same value of field intensity is obtained at each of the points, any one may be con- sidered satisfactory. K it is necessary to use an unsatisfactory site, a series of readings should be recorded at a number of different points in the neighborhood of the selected site, and detailed notes on the site conditions should be Appended to the recorded data.

MAKING AN INTERFERENCE SURVEY

An interference survey of a suspected area should begin with a series of measurements, at the frequencies under investigation, made with the appropriate pickup. It is customary in general surveys to make measurements at five frequencies in each band of the equipment with sufficient overlap to ensure complete coverage of all bands. If a station or service is found operating on the frequency selected for meas- urement, move sufficiently away in frequency to avoid sidebands of the station. The survey report should, however, note the frequency and field intensity of signals from the station. Certain types of interference surveys re- quire scanning an entire band for evidence of peaks or minima. Any such peaks or minima found must be measured and noted in the survey report.

During the survey, the received signals should be aurally monitored at a volume level that will enable identification of the signal or interference.

Three-point fixes on each source of inter- ference enable the geographic location to be determined by triangulation. Investigate each interference source, moving the RI-FI meter as close as is practical to the source to as- certain the distant fix. When the location has been narrowed down to a small area, use the loop probe to further determine the location of the offending equipment or power line. If the interference is found to be a power line or other current- carrying conductors, use

the RI-FI meter as a two-terminal voltmeter to determine the amount of conducted inter- ference on the line. Standard safety precau- tions should be considered when connecting to power lines of any equipment, which may be energized from a switch not under the control of the operator of the radio interference meas- uring set. All connections should be made with the power disconnected from the lines of the equipment under test.

Standardizing Gain

The operator must standardize the gain of the Radio Interference- Field Intensity Meter IM-37A/PRM-1 prior to taking a series of measurements on any one frequency. The op- erator can detect any radical change in sensi- tivity of the unit because this condition will necessitate a CAL control setting at a point greatly different from that normally used to ob- tain the standard gain.

Measuring Sine Wave Signals

Before making any type of measurements, the equipment must be standardized as just discussed. After this procedure has been ac- complished the measurement of sine-wave volt- ages should begin by turning the function switch to the FI position for a rms reading of a CW signal, or to the QP or PEAK positions when the carrier plus modulation is to be measured.

Adjust the position of the attenuator control until the meter reads within the scale range, preferably in the upper portion of the meter scale.

The signal being measured should be close to the frequency of gain standardization, as described above. Otherwise, it will be neces- sary to standardize the gain at the new fre- quency before a measurement can be accurately

made.

To determine the signal strength, read the indicating meter in microvolts, and multiply this reading by the correction factor obtained from the charts. This product is then multi- plied by the attenuator control setting.

OTHER APPLICATION OF THE RI-FI METER

The use of the RI-FI meter previously dis- cussed represents a single test application of the equipment. With a knowledge of the function

55

ELECTRONICS TECHNICIAN 3 & 2

and circuits of the operating controls con- sidered earlier, the ET should recognize the fact that the RI-FI meter makes itself applica- ble to many test situations.

Measurement as a null instrument in con- junction with r-f bridges and slotted lines, which operate in the 20 to 400 mc frequency range, is possible. Extremely short leads, preferably shielded, must be used and care must be taken to assure proper impedance matching.

Checking the gain of a radio frequency stage in radio equipment by measuring the voltage input to the stage and the signal out- put of the stage, is another use. It should be noted that the RI-FI meter shunts approxi- mately 50 ohms across the circuit and may upset the stage under test unless appropriately isolated.

You may also check the voltage of any 50-ohm transmission line up to one volt, pro- vided the transmission line is properly ter- minated. The voltage rating (d-c or a-c power frequencies) that may be applied to the input without damage to the input circuits should not be exceeded.

Another use is determining the loss in a coaxial line connected to a signal generator by comparing the signal level at the input and output ends of the line. The appropriate im- pedance matching network must be used be- tween the line and the RI-FI meter. To mini- mize the effects of standing waves, the higher attenuation positions (X102, X103, and X104) should be used when practicable.

FREQUENCY STANDARD AN/URQ-9A

In recent years, dependence on limited quartz-supply sources stimulated instrumen- tation for crystal- saving devices. Although prompted by crystal- saving, this development also made possible substantially smaller equip- ments, with multi- channel features; and fur- nished a means of obtaining increased stabili- ties.

During the past few years, emphasis in crystal- synthesis development has shifted from crystal- saving capability to precision- frequency generation. For example, in electronic sys- tems today, a synthesizer is used in generating frequencies from a single crystal, internally available or externally supplied. Phase co- herence is a prerequisite of performance.

A synthesizer should contain a reference frequency with a stability of at least 1 part in 10^ part per day, and a means of trans- lating the reference frequency to the required output frequencies. To achieve ideal perform- ance (that is, to deliver one frequency at a time with no spurious output whatsoever), an ideal synthesizer should not contain elements such as oscillators, mixers, and multipliers. Amplification alone should be permissible; and amplifier linearity should be absolute. In real- ity, the mathematical functions of addition, subtraction, multiplication, and division must be performed in the translation of frequencies. The method of frequency division has an advantage over that of frequency multiplication. For example; assume that 2 mc and 16 mc are required to be generated; that, in one case, a 16 mc signal is available and that energy is required at 2 mc; and that, in the other case, a 2 mc signal is available when it is necessary to generate 16 mc. When a 2 mc signal must be generated from a 16 mc signal, and a fre- quency division of 8 is employed, the frequen- cies developed are harmonically related to the output with a wide frequency separation. How- ever, the multiplication of a 2 mc signal by 8 results in a 16 mc signal with sideband energies at 14 and 18 mc, which require fine tuning cir- cuits to prevent interaction.

Most frequency synthesizers essentially con- tain a mainvariable-frequency oscillator (VFO), which will be disciplined by two secondary oscillators of lower frequency, for example, a 10 kc VFO and a 1 kc VFO. All three oscilla- tors are phase locked to the stable crystal- controlled reference oscillator. Thus the stability of the S3mthesizer output frequencies equal that of the reference oscillator.

The Navy has in use today, transmitters and receivers with frequency S3mthesizers that require a highly accurate and stable frequency standard so that adjustments can be satis- factorily performed. One of these frequency standards is the AN/URQ-9 with a stability of 1 part in 10^ parts per day.

The Frequency Standard AN/URQ-9 (fig. 3-4), is a highly stable, multiple-purpose fre- quency standard designed for continuous- duty use aboard ship and at shore facilities. It provides three output frequencies (5 mc, 1 mc, and 100 kc) at a minimum of 1 volt. The frequency standard can be used for laboratory frequency measurements and to drive precision timing devices such as a time

56

iil

Chapter 3-USE OF SPECIAL TEST EQUIPMENT

TEST METER

TEST SWITCH FUNCTION CARD

OUTER OVEN HEATER (INDICATING LAMP)

BAT. POWER SOURCE (INDICATING LAMP)

AC POWER SOURCE (INDICATING LAMP)

100 KC OUTPUT (CONNECTOR)

IMC OUTPUT (CONNECTOR!

SMC OUTPUT (CONNECTOR)

162.5

Figure 3-4.— Frequency Standard, Front Panel Control Locations.

comparator. It can also be used as a standby oscillator unit for other frequency/time-base standards.

The equipment is designed to operate from a nominal 115 volt, 60 cps, single-phase ex- ternal power source capable of providing 240 watts (approximately 2.0 amps) during periods of maximum battery charging. A battery, which is built into the equipment, is automatically switched into the circuit to maintain operation in the event the external power source fails or is disconnected. When fully charged, the battery is capable of operating the frequency standard for two hours.

The frequency standard consists of three major assemblies (fig. 3-5), a radio-frequency oscillator assembly, a power supply assembly, and a standby battery assembly.

The r-f oscillator assembly contains the crystal, frequency-determining circuit, and am- plifiers. The oscillator-amplifier generates a

5.0 mc signal which is fed to the 5.0 mc to 1.0 mc frequency divider. There the signal is amplified and a portion fed to output con- nectors on the front and back panels of the set. The other portion of the 5.0 mc signal is reduced to a 1.0 mc signal by the frequency divider circuits. The 1.0 mc signal is then amplified and a portion is fed to output con- nectors on the front and back panels of the set. The other portio.i of the 1.0 mc signal is fed to the 1.0 mc to 100 kc frequency divider where it is reduced to a 100 kc signal. The 100 kc signal is amplified and fed to output connectors on the front and back panels of the frequency standard.

The power supply assembly and the regulator-converter in the r-f oscillator as- sembly provide the regulated and unregulated voltages required by the set. If the external power source fails, or the power supply assembly develops a trouble, the set

57

ELECTRONICS TECHNICIAN 3 & 2

POWER SUPPLY ASSEMBLY

REFERENCE VOLTAGE

1

II5V I

60CPS

POWER TRANSFORMER

RECTIFIER

-I I

SATURABLE

REACTOR

CONTROLLED

BRIDGE

RECTIFIER

CONTROL

TRANSISTOR AMPLIFIER

26.5 V DC REGULATED

I

REGULATED 26.5 V DC

£'■

TRANSFER iPPP 1 RELAY "-W-cW

BATTERY TEMPERATURE COMPENSATION^

STANDBY BATTERY ASSEMBLY

26.8V DC Nl CAD BATTERY

LOW

VOLTAGE

DISCONNECT

^C BATTER1

< "FLOATS'

^-9 1

n I 1 1

26 5 V DC REGULATED

DC REGULATOR AND CONVERTER

.|-

RF OSCILLATOR ASSEMBLY I ^ ^ ^ ^

OUTER OVEN TEMP |-- CONTROLLER

REG 20 V DC

OVEN AND

TRANSISTOR

POWER

INNER OVEN TEMP U — CONTROLLER

I

I I I I

L_'°°^2?_?i®"'-*^^'' •''-*TE SUPPLY

1

I

♦

I !

[__ REGULATED 18 V DC-VT HEATERS j

HEATER WINDING

^AA»

5.0 MC OSCILLATOR- AMPLIFIER AND OVENS

^AA^

HEATER WINDING

5.0 MC TO I.OMC

FREQUENCY DIVIDER

■;-5

«-*

I.OMC TO 100 KC

FREQUENCY DIVIDER

TlO

5 0MC OUTPUT

I lOMC OUTPUT

^\r

I 100 KC I OUTPUT

rv

@

.J

Figure 3-5.— Frequency Standard, Functional Block Diagram.

162.6

automatically switches over to battery opera- tion. The frequency standard will operate from the battery for approximately two hours.

The frequency standard will be received by a calibration laboratory prior to being in- stalled at the using activity. The calibration laboratory technicians will perform initial op- eration and calibration tests on the set and it will then be transferred to the using activity without being turned off (operating on the standby battery). Once the frequency standard is in operation and is calibrated, it must not be allowed to stop operating as this will cause the ovens to cool and will alter the operating frequency of the crystal. If the set does get turned off, it should be returned to the calibra-

tion laboratory for re- calibration; or, if the set is installed at a shore facility or aboard a ship that is in port, it may be allowed to run for one week and checked by the calibra- tion activity for stability and correct fre- quency before being placed in service.

ELECTRONIC COUNTER 524D

A COUNTER type frequency meter (fig. 3-6), Electronic Counter 524D (Hewlett-Packard), can measure frequencies from 10 cps to 10.1 mega- cycles and display the readings in digital form on an eight-place indicating system. In addi- tion to making direct frequency measurements, the counter can measure periods (0 cps to 100

58

Chapter 3- USE OF SPECIAL TEST EQUIPMENT

70-35 Figure 3-6.— Electronic Counter, 524D.

kc), frequency ratios, and total events. A self- check feature enables an operator to verify instrument operation for most types of meas- urements. The internal oscillator is stable within 5 parts of 10^ per week. Thus these counters make good secondary frequency stand- ards.

To increase the range of measurement, seven accessory plug- in units (not shown) are avail- able. Frequency Converter Units, Models 525A, B, and C, increase the frequency range from 10.1 to 100 mc, 100 to 220 mc, and 100 to 510 mc respectively. Video Amplifier unit 526A increases the basic set sensitivity to 10 mv in the range of from 10 cps to 10.1 mc; Time In- terval unit 526B permits measuring time in- tervals from 1 lusec to 10"^ seconds; Period Multiplier unit 526C extends the period meas- jurement range up to 10,000 periods of unknown frequency; and Phase unit 526D permits meas- uring phase angle with an accuracy approach- ing t 0.1°. In addition to the plug-ins, the Model 540B Transfer Oscillator extends, as a companion instrument, the frequency range up to 12.4 megacycles (109 accuracy).

To measure frequency the basic circuit arrangement of the Electronic counter is shown in figure 3-7. For frequency measurement the

signal is fed through a Signal Gate to a series of digital type counters. A precision time in- terval obtained from the Time Base Section opens and closes the Signal Gate for an ex- tremely accurate period of time, for example, 1 second. The counters count the number of cycles entering through the gate during the 1- second interval and then display the total. The answer is read directly as the number of kilo- cycles occurring during the 1-second interval. The period of time the Signal Gate remains open is set by the FREQUENCY UNIT switch (not shown). For each position of the FREQUENCY UNIT switch the illuminated decimal point is automatically positioned so that the answer is always read directly in kilocycles. The answer is automatically displayed for a period of time determined by gate time or the setting of the DISPLAY TIME control on the front panel, which- ever is greater.

To measure a period or time interval the application of the two signals reverses as shown by the dotted lines in figure 3-7. The period or time interval to be measured is connected to open and close the Signal Gate while one of the standard frequencies from the Time Base Section is passed through the Signal Gate to the counters. When measuring period, one cycle of the incom- ing signal opens the gate, the next cycle closes it. The number of cycles of the standard fre- quency from the Time Base that occurred during the period are then indicated on the counters. The standard frequencies obtained from the Time Base have been selected so that the answer to the measured period will always be displayed in direct- reading units of time: seconds, milli- seconds, or microseconds.

Provision is also made in the circuit to per- mit measurement of the average of 10 periods

					COUNTERS
INPUT	SIGNAL GATE
	\ / \ / \/ X /\ / \
		-.
TIME BASE GENERATOR	CLOSING SIGNAL

70.36 Figure 3-7.— Basic block diagram of the 524D.

59

ELECTRONICS TECHNICIAN 3 & 2

of the unknown frequency. Higher accuracy can thus be obtained than with single period measurements.

The accuracy of frequency measurements is determined by an internal oscillator and by a possible error of + 1 count that is inherent in the gate and counter type of instrument. At low frequencies, greater accuracy can be ob- tained by measuring the period of the signal than by measuring the frequency directly.

The block diagram (fig. 3-8, A) shows the circuit arrangement of the basic counter when measuring frequencies in the range of 10 cps to 10.1 mc. To measure frequencies up to 510 mc, one of three frequency converter units is required (fig. 3-8, B). As stated above, the 525C Frequency Converter unit is used between 100 and 510 mc. In these frequency convert- ers the input signal is mixed with a harmonic of 10 mc so that the difference between the signal and the harmonic is not more than 10.1 mc. The difference frequency is counted and displayed. By adding the count displayed by the counter to the known 10 mc harmonic the input signal frequency is determined.

All three frequency converters have tuning systems to indicate the correct mixing fre- quency. However, if the mixing frequency is within 1 mc of the unknown frequency, there is a possibility of two answers, for you may not know whether to add or subtract the dis- played reading from the mixing frequency. In such cases, make additional measurements using the two adjacent mixing frequencies to determine the unknown frequency. When mak- ing the final measurement choose a mixing frequency which is at least 100 kc away from the unknown.

When measuring frequency, the counter will count sine waves, rectangular waves, and posi- tive pulses. To measure the frequency of nega- tive pulses, adjustment of a FREQUENCY sen- sitivity control is necessary. This control is a screwdriver adjustment located on the front panel.

When the counter is set for PERIOD meas- urements, the time base and the signal input circuits are interchanged from their frequency measurement positions (fig. 3-8,C), With the circuits so connected, the counters count the output of the time base for the period of the unknown input signal. Thus the standard fre- quencies generated in the time base are used as units of time to measure the unknown period

in terms of microseconds, milliseconds, or seconds.

The accuracy of period measurements is largely determined by the accuracy with which triggering occurs at the same point on con- secutive cycles of signal voltages having a slow rate-of-rise. Note that when the signal- to-noise ratio improves, the triggering accuracy also improves. Averaged over ten periods, the single-period error is reduced by a factor of ten. Lf you use the 526C Period Multiplier unit, the error is reduced an additional factor of ten for each factor of ten you extend the measure- ment. The accuracy of triggering is consider- ably improved when the waveforms being meas- ured have a fast rise time. For example, you can obtain a significant reduction in error if you apply square waves instead of sine waves to the input.

In order to follow the slowest- changing waveforms, the period measurement input cir- cuits are direct- coupled and are adjusted to trigger at the zero-volt crossing of a negative- going voltage. Thus any d-c component in the input signal will shift the triggering level so that the maximum slope no longer occurs at the zero-volt level, resulting in a loss of accuracy. If the d-c component is large enough, there may be no triggering at all. An external generator can be used in place of the time base generator for period measurements.

The counter can be used to measure the RATIO of two frequencies. The higher frequency is passed through the signal gate to the counters and is counted for a period of time determined by either one period or ten periods of the lower frequency, which controls the opening and clos- ing of the gate (fig. 3-8,D).

Ratio measurement accuracy is determined by the same factors as period measurement accuracy: consistency of triggering by the lower input frequency and the inherent error of t 1 count of the higher frequency. The 526C Period Multiplier unit is used to reduce the error by extending the number of periods of the lower frequency over which the measurement is made. For each factor of ten the measurement is extended, the error is decreased by a factor of ten.

Although the time base generator is not used during ratio measurements, you cannot make ratio measurements if the time base generator is not operating. The counter has a holdoff circuit which disables the signal gate if the time base generator fails.

60

Chapter 3- USE OF SPECIAL TEST EQUIPMENT

INPUT

@-

SIGNAL GATE

COUNTERS

I, ,-.001, .01. . J. I, OR 10 SECONDS

TIME BASE GENERATOR

FUNCTION SELECTOR

- FREOUENCy -

FREQUENCY UNIT

'%'

TEN PERIOD O

PERIOD

@H

SIGNAL INPUT

n

DECADE DIVIDER

®-

STD FREQ OUTPUT

SIGNAL GATE

COUNTERS

A FREQUENCY MEASUREMENTS BELOW 10 MEGACYCLES

^ FREOUewCY TO BE COUNTED

, DIFFERENCE FREQUENCY

@-J

INPUT

FREQUENCY

CONVERTER

UNIT

SIGNAL GATE

FUNCTION SELECTOR

- FREQUENCY

COUNTERS

TIME UNIT

FUNCTION SELECTOR

D RATIO MEASUREMENTS

TIME INTERVAL PLUG-IN UNIT

(^

STOP INPUT

,^" .001. .01. .1. I. OR 10 SECONDS

TIME BASE GENERATOR

FREQUENCY UNIT

FREQUENCY MEASUREMENTS ABOVE 10 MEGACYCLES

TEN PERIOD PERIOD

^

START INPUT

—f 1

•°"* DSERJ

-/ ;

GATE OPENING SfGNAL-

10 MC, lOOKC IKC OR 10 CPS ~ - -

a

GATE CLOSfNG SIGNAL

SIGNAL

GATE

COUNTERS

TIME BASE GENERATOR

@-<

SIGNAL INPUT

DECADE DIVIDER

,_CATE OPENING AND CLOSING SIGNAL

IOjMC. 100 KC, I ICC OR 10 CPS .

TIME UNIT

SIGNAL GATE

COUNTERS

TIME BASE GENERATOR

FUNCTION SELECTOR

FUNCTION SELECTOR

-EXT.

TO CPS' ^<Z^<^ ^lOMC 1 KC 100 KC

I TIME INTERVAL MEASUREMENTS

@-

SIGNAL GATE

I KC 100 KC

C PERIOD MEASUREMENTS

STD FREQ OUTPUT

OPEN O MANUAL GATE ^ o closed

FUNCTION SELECTOR

COUNTERS

f TOTALIZING

Figure 3-8.— Test measurement, block diagram. 61

70.37

ELECTRONICS TECHNICIAN 3 & 2

To make TIME INTERVAL measurements (fig. 3-8,E), the 526B Time Interval unit must be installed. Time interval measurements are similar to period measurements except that the points on the signal waveforms at which the measurement starts and stops are adjustable. The adjustable threshold feature allows you to make measurements from one part of the same waveform or to use separate waveforms as start and stop signals.

As in the case of period measurements, the input signals control the opening and closing of the gate while the standard frequencies are passed to the counters (fig. 3-8,E). Thus the accurate frequencies generated in the time base are used as units of time to measure the unknown interval in terms of microseconds, milliseconds, or seconds.

The threshold-selecting controls adjust the start and stop channels so that they will be actuated only by signals of predetermined po- larity, amplitude, and slope. Time interval measurements begin when the start signal crosses the selected start threshold value in the selected direction and end when the stop signal crosses the selected stop threshold value m the selected direction. The threshold con- trols are only approximately calibrated, and in some applications you will have to take special precautions in order to obtain the de- sired interval.

If you use an uncomplicated waveform as the start and/or stop signal, the setting of the threshold controls is not critical. For example If you use a sharp pulse like that shown in figure 3-9,A, there will be little difference whether the measurement begins at point A or

B

A

RO

* SIMPLE WAVEFORM SHOWING TWO POS- SIBLE VOLTAGE LEVELS AT WHICH A TIME INTERVAL MEASUREMENT MAY BE STARTED

B. However, if you use a more complex wave- form like that shown in fig. 3-9,B, to measure the interval X, set the threshold controls near zero as a preliminary adjustment. As you ad- just first the start and then the stop threshold controls, you will notice definite changes in the measured time interval. Thus you know that the start and stop thresholds are above the step and that the indicated time interval is actually X.

It is highly desirable to examine both start and stop signals on a d-c coupled oscilloscope before you attempt a measurement. In this way you can determine that no spurious signals exist, and you will know how carefully you must set the threshold controls.

The 526B Time Interval unit may also be used as a high-speed totalizer capable of count- ing at a maximum rate of 10.1 million events per second. The basic circuit arrangement is indicated in figure 3-8, F.

With a 526D Phase unit plugged into the counter, the phase angle between two signals of identical frequency, in the range from 1 cps to 20 kc, may be measured. This unit is use- ful for investigating, at various points in a circuit, the phase a signal has with respect to the phase it had at the input. Connect the ref- erence signal to the REFERENCE INPUT, and the signal whose phase is under investigation to the UNKNOWN INPUT. If the frequency of the signal is 400 cpst4 cps, phase angle is read directly in tenths of a degree. For a signal of some other frequency in the rated range, the information is read in time units, with resolu- tion up to O.lMsec. For all phase measure- ments, set the phase unit PHASE/ PERIOD

TWO POSSIBLE TIME INTERVAL MEASUREMENTS OF A SINGLE COM- PLEX WAVEFORM

Figure 3-9.— Time interval waveforms. 62

70.38

Chapter 3-USE OF SPECIAL TEST EQUIPMENT

switch to PHASE, the REFERENCE LEAD/ LAG switch to the type of measurement de- ired, and the counter FUNCTION SELECTOR 10 PERIOD.

In general, circuit action for a phase meas- arement is similar to that for a time interval measurement. Trigger circuits in the Phase unit supply the pulses which open and close the signal gate in the counter. Arrangement of the circuits will be similar to that shown in figure 3-8, E, for time interval measurements.

A recommended method of TUNING RADIO RECEIVERS USING A FREQUENCY COUNTER has been included in the EIB, No, 569. This method will soon become the accepted proce- dure for all such tuning.

DIGITAL READOUT ELECTRONIC COUNTER AN/USM-207

The AN/USM-207 is a portable, solid-state electronic counter for precisely measuring and

displaying on an 9-digit numerical readout the frequency and period of a cyclic electrical sig- nal, the frequency ratio of two signals, the time interval between two points on the same or dif- ferent signals, and the totalnumber of electrical impulses (totalizing). The counter also provides the following types of output signals:

1. Standard signals from 0.1 cps to lOmcin decade steps derived from a 1 mc frequency standard, frequency dividers, and a frequency multiplier;

2. Input signals divided in frequency by fac- tors from 10 to 10^ by a frequency divider;

3. Digital data of the measurement in four- line binary- coded- decimal form with decimal point and control signals for operation of print- ers, data recorders, or control devices; and

4. A 1 mc output from a frequency standard.

GENERAL DESCRIPTION OF AN/USM-207

The AN/USM-207 (figure 3-10) consists of a major counter assembly, two plug- in

RADIO FREQUENCY OSCILLATOR 0-I267/USM-207 (HIDDEN)

ELECTRONIC FREQUENCY CONVERTER CV-I92I/USM-207

PANEL PROTECTOR

DIGITAL READOUT ELECTRONIC COUNTER CP-8I4/USM-207

PANEL PROTECTOR

POWER LIGHT

RF CABLE

CONNECTOR

ADAPTER

UG-274B/U

CONNECTOR

ADAPTER

UG-I035/U

DIGITAL READOUT ELECTRONIC COUNTER AN/USM-207

CONNECTOR

ADAPTER

UG-255/U

PRINTED CIRCUIT BOARD EXTRACTOR

PRINTED CIRCUIT BOARD EXTENDER

162.7

Figure 3-10.-Digital readout electronic counter AN/USM-207,

63

ELECTRONICS TECHNICIAN 3 & 2

assemblies which install in recesses on the front and rear panel, and a group of accessory cables and connectors stored in the detachable front cover.

Digital Readout Electronic Counter CP-814/USM-207

The major assembly Digital Readout Elec- tronic Counter CP-814/USM-207 contains the input amplifiers; gate control; display; reset and transfer control; frequency multipliers; time base dividers; decade and readout boards; numerical display tubes; decimal point and units indicators; power supply and regulator; and con- trols associated with these circuits.

Radio Frequency Oscillator O-1267/USM-207

The Radio Frequency Oscillator 0-1267/ USM-207 plug-in assembly develops a 1 mc sig- nal and includes its own power supply. The oscillator includes the 1 mc output receptable which may be used as a source of that fre- quency when the oscillator is connected to a-c power through the basic counter or when connected to the power line independently of the counter. The counter may be operated with- out the oscillator in totalizing, scaling the input signal, time interval with external clock, and frequency ratio measurements. For other measurements the counter does not require the oscillator when a separate external 100 kc or 1 mc signal is connected. In either of these two situations the oscillator may be left in the counter or removed. The oscillator plugs into the right rear of the counter.

Electronic Frequency Converter CV- 1921/ USM-207

The Electronic Frequency Converter CV- 1921/USM-207 plug-in assembly permits meas- urement of frequencies up to 500 mc using the heterodyne principle. The unit consists of the broadband amplifier, mixer, multiplier, and controls and indicators associated with these circuits. When measurements other than het- .erodyne frequency measurements are made, the converter is not required, but need not be removed. The converter also permits the measurement of signals from 35 mc to 100 mc with a greater sensitivity than available with the basic counter. The converter plugs into the right front of the counter.

FUNCTIONAL DESCRIPTION

Figure 3-11 is the overall functional bloch diagram of the counter. To make a measure- ment, requires two types of information; a counl signal, and a gate control signal. These two sig nals may be generated within the instrument or they may be supplied from outside sources. The type of measurement the counter will make depends upon the relationship of these two sig- nals. In any function the instrument counts the count signal for a period of time de- termined by the gate control signal. Routing of these signals within the instrument is accom- plished by logic circuits. These logic circuits are controlled by means of the front panel controls.

The radio frequency oscillator (0-1267/USM- 207) generates a signal of precise frequency for use throughout the counter or to provide a precise 1 mc signal for use outside the equipment. The electronic frequency converter accepts radio frequencies between 100 mc and 500 mc and converts them to radio frequencies between 5 mc and 100 mc for measurement by the basic counter.

The "A" amplifier amplifies the A input signal or the output of the converter for use throughout the counter.

The "B" amplifier amplifies and shapes the B input signal for use throughout the counter. The "C" amplifier amplifies and shapes the C input signal for use throughout the counter. The 10 mc and 1 mc multiplier multiplies the frequency and shapes the signal generated