AN-URM-157A_test_harness_serv_TM11-6625-622-40_1973.pdf

TM 11-6625-622-40 TECHNICAL MANUAL GENERAL SUPPORT MAINTENANCE MANUAL TEST HARNESS, RADIO SET AN/URM-157 AND AN/URM-157A HEADQUARTERS, DEPARTMENT OF THE ARMY JULY 1973 WARNING DEATH OR SERIOUS lNJURY may result from hazards in this equipment unless proper safety measures are observed when operating and maintain- ing the equipment. 117 VAC exists when the equipment is energized. TM 11-6625-622-40 C1 CHANGE HEADQUARTERS DEPARTMENT OF THE ARMY WASHINGTON, DC, 28 December 1976 General Support Maintenance Manual TEST HARNESS, RADIO SET AN/URM-157 (NSN 6625-00-766-4685) AND AN/URM-157A (NSN 6625-00-236-1557) TM 11-6625-622-40, 2 July 1973, is changed as follows: 1. The title is changed as shown above. 2. New or changed material is indicated by a vertical bar. 3. Remove and insert pages as indicated below. Remove 1-1 2-1 and 2-2 3-1 and 3-2 3-13 and 3-14 3-17 and 3-18 A-1 4. File this change sheet in front of the publication for reference purposes. By Order of the Secretary of the Army: Official: PAUL T. SMITH Major General, United States Army The Adjutant General Insert 1-1/( 1-2 blank) 2-1 and 2-2 3-1 and 3-2 3-13 3-17 and 3-18 A-1/(A-2 blank) BERNARD W. ROGERS General United States Army Chief of Staff Distribution: To be distributed in accordance with DA Form 12-36A, Direct and General Support maintenance requirements for AN/URM-157. No. 1 *TM 11-6625-622-40 TECHNICAL MA N U A L HEADQUARTERS DEPARTMENT OF THE ARMY No. 11-6625-622-40WASHINGTON, D.C., 2 July 1979 GENERAL SUPPORT MAINTENANCE MANUAL TEST HARNESS, RADIO SET AN/URM-157 AND AN/URM-157A CHAPTER 1. Section I. II. CHAPTER 2. 3. Section I II. III. IV. APPENDIX A. Paragraph INTRODUCTION General Scope - - - - - 1-1 Maintenance forms and records - - - - 1-2 Destruction of equipment prevent enemy use - - - 1-3 Administrative storage - - - - - 1-4 Reporting of errors - - - - - 1-5 Description and data Description - - - - - 1-6 Tabulated data - - - - - 1-7 FUNCTIONING OF EQUIPMENT General - - - - - - - - -2-1 Ac distribution circuit - - - - 2-2 Dc distribution circuit - - - - 2-8 Rf load - - - - - 2-4 Resistive-capacitive load - - - - 2-5 Audio circuits - - - - - 2-6 TUNE POWER switch - - - - 2-7 Control, Radio Set C-3940/ARC-94 - - - 2-8 Directional wattmeter - - - - 2-9 GENERAL SUPPORT MAINTENANCE INSTRUCTIONS General General instructions - - - - - 3-1 Organization of troubleshooting procedures - - - 3-2 Tools and test equipment required - - - 3-3 Troubleshooting Localizing troubles - - - - - 3-4 Troubleshooting directional wattmeter - - - 3-6 Maintenance of AN/URM-157 General parts replacement techniques - - - 3-6 Replacement data - - - - - 3-7 General support testing procedures General - - - 3-8 Test equipment and materials required - - 3-9 Modification work orders - - - 3-10 Physical tests and inspections - - 3-11 Test Harness, Radio Set AN/URM-157 continuity and short-circuit tests -3-12 Test Harness, Radio Set AN/URM-167A continuity and short-circuit tests -3-13 Directional wattmeter calibration test - - -3-14 Test data summary - - - -3-15 REFERENCES - - - - Page 1-1 1-1 1-1 1-1 1-1 1-1 1-1 2-1 2-1 2-1 2-1 2-1 2-2 2-2 2-2 2-3 3-1 3-1 3-1 3-1 9-6 3-8 3-8 3-8 3-8 3-8 3-8 3-9 3-11 3-13 3-13 A-1 This manual suspersedes TM 11-6625-622-45, 27 May 1965, Including all changes i TM 11-6625-622-40 LIST OF ILLUSTRATIONS Figure No. 2-1 2-2 3-1 3-2 3-3 3-4 3-5 3-6 3-7 3-8 3-9 3-10 3-11 3-12 3-18 3-14 3-15 3-16 Title Dummy antenna, schematic diagram - - - - - Directional wattmeter schematic diagram - - - - Test unit chassis, less dummy antenna, parts location - - - Test unit chassis, including dummy antenna, parts location - - - Directional wattmeter, parts locations and wiring diagram - - - Directional wattmeter test connection - - - - - Test Harness,Radio Set AN/URM-157 continuity and short-circuit test connections . - - Test Harness, Radio Set AN/URM-157A continuity and short-circuit test connections . . . . . . . . . . . . . . . . Test Harness, Radio Set AN/URM-157 directional wattmeter, calibration test connection . . . . . . . . . . . . Test Harness,RadioSetAN/URM-157A directional wattmeter, calibration test connection - Resistors, inductors, and capacitors color code marking for MIL-STD resistors, inductors and capacitors - - - - - Control,Radio Set C-8940/ARC-94, schematic diagram - - - Test Harness,Subassembly,TS-1949/URM-157, schematic diagram - - Test Mat Harness Subassembly TS-1949A/URM-157, schematic diagram - - - Cables W1 through W13, power cables, and rf cable, schematic diagram - - Control,RadioSetC-8940/ARC-94, wiring diagram - - - - Test Harness Subassembly, TS-1949/URM-157, wiring diagram - - - Test Harness Subassembly,TS-1949A/URM-157, wiring diagram - - - Page 2-2 2-4 3-4 3-6 3-7 3-7 3-15 3-16 3-17 3-18 Fold-In Fold-In Fold-In Fold-In Fold-In Fold-In Fold-In Fold-In ii TM 11-6625-622-40 CHAPTER 1 INTRODUCTION Section 1. GENERAL 1-1. Scope a. This manual covers general support maintenance for Test Harness, Radio Set AN/URM-157 and AN/URM-157A. It includes instructions appropriate to general support maintenance for troubleshooting, test- ing, aligning, and replacing maintenance parts. It also lists tools, materials, and test equipment for general support maintenance. b. The purpose, operation, and interoperation of the various circuits (electrical and electromechanical) in the AN/URM-157 and AN/URM-157A are explained in paragraphs 2-1 through 2-9. Familiarity with the equip- ment, how it works, and why it works the way it does are valuable tools in troubleshooting the equipment rapidly and effectively. 1-2. Maintenance Forms and Records Department of the Army forms and procedures used for equipment maintenance will be those prescribed by TM 38-750. 1-3. Destruction of Equipment to Prevent Enemy Use Refer to TM 750-2442 for proper procedures for destruction of this equipment to prevent enemy use. 1-4. Administrative Storage Refer to TM 740-90-1 for administrative storage re- quirements. 1-5. Reporting of Errors The reporting of errors, omissions, and recommenda- tions for improving this publication by the individual user is encouraged. Reports should be submitted on DA Form 2028 (Recommended Changes to Publications and Blank Forms) and forwarded direct to Commander, US Army Electronics Command, ATTN: DRSEL-MA-Q, Fort Monmouth, NJ 07703. Section Il. DESCRIPTION AND DATA 1-6. Description1-7. Tabulated Data Refer to TM 11-6625-622-12 for description of the Refer to TM 11-6625-622-12 for operator and organiza- tional maintenance of the AN/URM-157 and AN/URM-157 and AN/URM-157A.AN/URM-157A. Change 1 1-1 TM 11-6625-622-40 CHAPTER 2 FUNCTIONING OF EQUIPMENT 2-1. General The test unit (main component of Test Harness, Radio Set AN/URM-157 or AN/URM-157A) is used in the test- ing and troubleshooting of Receiver-Transmitter, Radio RT-698/ARC-102. It has both alternating-current (ac) and direct-current (dc) power distribution circuits. The control unit controls frequency, radiofrequency, radiofrequency (rf) sensitivity, and mode of operation of the receiver-transmitter. The directional wattmeter provides for the measurement of foward and reflected transmitter output power. The 50-ohm load is used as matched load for the receiver-transmitter. A dummy antenna is provided when a resistive-capacitive load is needed. Audio jacks in the test unit can be used in place of audio jacks in the receiver-transmitter. 2-2. Ac Distribution Circuit (fig. 3-11) The 115-volt, 3-phase,400-Hertz(Hz) input poweris ap- plied to switch S3 of the test unit through AC IN con- nector J7, 1 FUSE F1, 2 FUSE F2, and 3 FUSE F3. The 1, 2, 3 fuses are rated at 5 amperes each, and protect both the receiver-transmitter under test and the test unit. When at ON, AC switch S3 ap- plies power to 618T-2-OFF-618T-3 switch S1. When switch S1 is at 618T-3 (center position OFF), phases 1 and 2 are open. (Three-phase power is not used by the RT-698/ARC-102.) Phase 3 is fed around switch S1 to 516H-1 connector J5 pin 16, where it is tied to 115 V, 400 CPS OUT outlet J18. Three-phase, 115-volt, 400-Hz ac power is applied to the receiver transmitter under test through 618T- 2/3 connector J1 pin 12. Ac power is returned from the receiver-transmitter, through con- nector J1 pin 11 and through the test unit, to ANT. CPLR connector J6 pin S, where it is applied to the an- tenna coupler being used. 2-3. Dc Distribution Circuit (fig. 3-11) The 27.5 volts dc is applied to the test unit, through DC IN connector J4, to the DC POWER switch and circuit breaker CB1. Circuit breaker CB1 is rated at 45 am- peres. When DC POWER circuit breaker CB1 is at ON, dc is applied to 516H-1 connector J5 pin 23 and to 618T-2-OFF-618T-3 switch S1. When switch S1 is at 618T-3, seven branches from switch S1, pins 11,8,5, and 2 conduct dc power, through 618T- 2/3 connector J1, pins 1,13,2, 14, 3, 15, and 17, to the high-voltage power sup- ply module of the receiver-transmitter under test. DC power, available at the input of S1, is connected through fuse F4 to connector J1, pins 4 and 16. Fuse F4 is rated at 10 amperes, and protects the 27.5-volt dc con- trol circuitry of the receiver-transmitter. The 27.5 volts dc is fed back to the test unit from the receiver- transmitter, through connector J1 pin 56. One line con- nects to ANT. CPLR connector J6, pins, r, s, and t; another branch connects to KEY INTLK switch S7, pin 1, and another branch connects to J2 pin 56. If switch S7 is at BY PASS, 27.5 volts dc is connected to connec- tor J6 pin X, and one branch is fed back to the receiver- transmitter key interlock circuit, through connector J1 pin 5. 2-4. Rf Load (fig. 2-1) The 50-ohm resistive rf load is available at 50 RF LOAD connector J9 on the test unit top panel. The 50- ohm load is provided by a series-parallel connection of 50-ohm resistors R1 through R4. 2-5. Resistive-Capacitive Load (fig. 2-1) A resistive-capacitive load is available between DUM- MY ANTENNA INPUT jack J15 and ground jack J16. It consists of a parallel combination of 75- micromicrofarad (f) capacitors C1 and C2 in series with the 50-ohm rf load. Change 1 2-1 TM 11-6625-622-40 NOTES: 1.INDICATES EQUIPMENT MARKINGS. 2. UNLESS OTHERWISE INDICATED ALL RESISTANCE VALUES ARE IN OHMS, ALL CAPACITANCE VALUES ARE IN UUF. TM6625-622-45-11 S5, terminal 2 and jack J19, pin b. Jack J11 on the test unit is used instead of PHONE jack J1 of the receiver-transmitter. A 300-ohm load may be placed in the audio output circuitry of the receiver-transmitter by switch S5. c. Key Line Circuit. The key line circuit which isused for remote keying of the receiver- transmitter passes through the test unit as fol- lows: From jack J12, terminal 2, to switch S6 terminal 3. If S6 is at 714E2/3, connection is made to S6 terminal 2 which is connected to ANT. CPLR jack J6 pins N, P, and R, 516H1, con- nector J5 pin 1, and to the receiver-transmitter, through 618T2/3 connector J1 pin 55. Connec- tion is also made from jack J12 terminal 2 to jack J19 pin m. If switch S5 of the control unit is at AM, USB, or LSB, the key line is returned through jack J19 pin q to switch S6 terminal 1. Figure 2-1. Dummy antenna, schematic diagram. 2-6. Audio Circuits (fig. 3-11) a. Audio Inputs to Receiver-Transmitter. A balanced audio input is supplied to the receiver- transmitter from 600 BAL AUDIO IN jack J8. The audio goes from jack J8, through 618T2/3 connector J1 pins 53 and 37, to the AM/audio amplifier module of the receiver-transmitter. An unbalanced audio input is supplied to the receiver- transmitter from MIKE jack J12. The audio goes from terminal 1 of J12, through 618T2/3 connec- tor J1 pin 54, to the AM/audio amplifier module of the receiver-transmitter. MIKE jack J12 on the test unit can be used instead of MIC jack J2 of the receiver-transmitter. b. Audio Outputs from Receiver-Transmitter. The audio output of the receiver-transmitter may be monitored at HEADSET jack J11. The audio is supplied through connector J1, pins 57 and 58. From connector J1 pin 58, audio goes to jack J19 pin a, which is jumpered to jack J19 pin c through the control unit. Pin c of jack J19 is connected to jack J11 terminal 1. From pin 57 of connector J1, the audio is connected to jack J11, terminal 2,300 AUDIO LOAD switch When S6 is at 714E2/3, connection is again made to terminal 2 of S6, completing the key line circuit. KEY switch S9 is connected to jack J12 terminal 2 and places a ground on the key line circuit in either the up or down position. 2-7. TUNE POWER Switch (fig. 3-11) TUNE POWER switch S4 connects to J1 pin 10 and, when depressed, grounds the receiver-trans- mitter tune powerline to check the functioning of the tune circuitry within the receiver-trans- mitter. Switch S4 is not used with antenna couplers. To avoid damage to the receiver-trans- mitter, it should not be depre