SCR-284A_serv_user_TM11-275_1945.pdf

War Department Technical Manual TM 11-275 Thi Manual supersedes TM 11-275,5 April 1943, TiU 1I-275-A, 22 June 1943, and T1111-275, 2.1 August 1943 and Section III of War lJepartment Training Circular No.3, 194.1. RADIO SET SCR-284-A War DepartJnel1t 24 J al1uary 1944 Revised 5 April 1945 VAR DEPARTIENT, VASHINGTON 25, D. C., 24 January 1943. TM 11-275, Radio Set SCR-284-A, is published for the information and guidance of all concerned. LA. G. 300.7 (19 JAN. 44) By ORDER OF THE SECRETARY OF WAR: OFFICIAL: J. A. ULIO, M ajar General, The Adjutant General. DISTRIBUTION: IBn and H 3, 5, 6, 7 (5); Ie 3, 5, 6, 7, 11, (10). (For explanation of symbols see FI 21-6.) II G. C. MARSHALL, Chief of S taff TABLE OF CONTENTS SECTION I. DESCRIPTION Par. 1. General . . 2. List of Component Parts 3. Sources of Power . . . 4. Input Power . . . . . 5. Description of Main Components SECTION II. INSTALLATION AND OPERATION 6. Initial Procedure . . . . . . 7. Vehicular Installation . . . . 8. Preparation for Vehicular Use 9. Field Installation . . . . . 10. Precautions Before Operation . 11. Operation . . . . . . . . . 12. Precautions Before Operation . SECTION III. FUNCTIONING OF PARTS 13. Receiver Controls and Their Functions 14. Receiver Circuit Functions . . . . . . . 15. Transmitter Controls and Their Functions 16. Transmitter Circuit Functions 17. Power Converter PE-I04-A . 18. Functioning of Optional Antennas 19. Power Unit PE-I03-A . . . . . 20. Generator GN -45-(*) . 21. Remote Control Unit RM-29-(*) SECTION IV. MAINTENANCE 22. Noise Suppression . . . . . . . . . . . . . . . . . . . . . . . . 23. Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . 24. Disassembly of Radio Receiver and Transmitter BC-654-A for Servicing . 25. Removal and Assembly of Parts . 26. Receiver Tubes . . . . . . . . . . 27. Transmitter Tubes . . 28. Receiver Performance Characteristics 29. Alignment of the Receiver . . . . . 30. Transmitter Performance Characteristics 31. Alignment of the Transmitter . . . . . 32. Generator GN-4S-(*) Voltage Regulator Adjustment 33. Lubrication of Equipment . . . . . . . 34. Moisture and Fungus Proofing SCR-284-A 3S. Power Converter PE-I04-A . . . . . . . 36. Receiver Audio Oscillation . . . . . . . 37. Breaking of Conductors in Cord CD-SOI-A 38. Protection of Equipment from Moisture . 39. Guard for 6/12 Volt Switch in Power Unit PE-I03-A 40. Aro-Over in Power Cord Connectors . . . . . . . . 41. Loudspeaker . . . . . . . . . . . . . . . . . . SECTION V. SUPPLEMENTARY DATA 42. Replaceable Parts for Transmitter Section of BC-654-A 43. Replaceable Parts for Receiver Section of BC-654-A 44. Replaceable Parts for Power Unit PE-I03-A 45. Replaceable Parts for Power Converter PE-I04-A 46. Replaceable Parts for Hand Generator GN-45-A 47. Replaceable Parts for Hand Generator GN-45-B 48. Miscellaneous Replaceable Parts for SCR-284-A . Page 1 1 2 2 3 6 6 8 10 11 11 15 16 16 19 22 27 29 29 32 33 35 35 35 36 36 38 47 47 49 51 52 52 53 54 54 54 55 55 55 55 59 72 81 85 89 90 91 III LIST OF ILLUSTRATIONS Figure Page 1. Radio Set SCR-284-A. . . . . . . . . . . . . . . . . . . . . vi 2. Radio Set SCR-284-A-Vehicular Installation Components . . . . : . . . . . . . . . . . . . . . . . . . . . . 3 3. Power Unit PE-103-A . . . . . . . . . . . . . . . . . 0 4 4. Generator GN-45-(*) . . . . . . . . . . 0 0 4 5. Remote Control RM-29-(*) . . . . . . 0 5 6. Field Installation of Radio Set SCR-284-A. . . 6 7. Radio Set SCR-284-A-Installed in Car Y2 Track, M2 . . . . . . . . . . . . . . . . 7 8. Radio Set SCR-284-A-Field Installation Components . . . . . . . . . . . . . . . . . 0 9 9. Receiver and Trans.mitter BC-654-A- Front Panels . . . . . . . . . . . . . . . . . . 0 12 10. Radio Frequency and Oscillator Circuit . . . . . 16 11. Intermediate and Beat Frequency Oscillator Circuit . . . . . . . 0 0 17 12. Audio Amplifier Circuit . . . . . . . 0 0 0 0 0 0 o. 18 13. A VC Circuit . . . . 0 0 19 14. Typical Calibration Chart . . . . . . . . . . . . . . . . 20 15. Audio Amplifier and Modulator Circuit . . . . . 22 16. Power Amplifier Output Circuit . . . . . . . . . 23 17. JIaster Control Switching for Circuits. . . . . . . 24 18. JIaster Oscillator- . Intermediate Power Amplifier Circuit . . . . . 26 19. Crystal Oscillator Circuit. . . . . . . . . . . . . . . . . . 26 20. Power Converter PE-104-A, Schematic Diagram . . . . . . . . . 0 0 o. 27 21. Power Converter PE-l04-A, Connection Diagram . 0 0 0 0 0 28 22. T-Shaped Antenna . 0 0 0 0 .00 0 0 29 23. Power Unit PE-103-A,. Schematic Diagram . . 0 0 0 0 0 0 o. 30 24. Power Unit PE-103-A, Connection Diagram . 0 0 o. 31 25. Generator GN-45-(A), Schematic Diagram . . 0 0 0 0 o. 31 26. Generator GN-45-(A), Connection Diagram . 0 0 0 0 0 o. 32 27. Remote Control RM-29-(*), Telephone Position . . . . . . 0 0 0 0 0 0 33 28. Remote Control RM-29-(*), Radio Position . . . . . . . . . . 0 0 33 29. Remote Control RM-29-(*), Through Position . . . . . . . . . . 0 0 0 0 0 0 33 30. Remote Control RM-29-(*), Schematic Diagram . . . 0 0 34 31. Remote Control RM-29-(*), Connection Diagram . . . . . . . . . . . . . . . . . . . . 34 32. Receiver Chassis (Top View) . . . . . . . . . . . . . . 48 33. Receiver Chassis (Bottom View) . . . . . . . . . . . . 48 34. Transmitter Chassis (Top View) . . . . . . . . . . 50 35. Transmitter Chassis (Bottom View) . . . . . . . . . 50 36. Dynamotor for Power Unit PE-103-A (Front View) . . . . . . . . . . . . . . . . . . . . . . . . . . 56 37. Dynamotor for Power Unit PE-103-A (Rear View) . . . . . . . . . . . . . . 0 0 0 0 0 56 38. Generator GN-45-(A), (Top cover removed) . . . . . . . . . . . . . . . . . 57 39. Generator GN-45-(A), IV and Case CS-41. . . . . . . . . . . . . . . . . . . . . . 57 Figure Page 40. Power Converter PE-104-A, (Bottom cover removed) . . 0 0 0 58 41. Remote Control Unit RM-29-A, (Case removed) . . . . . . . . 0 0 0 0 58 42-A Receiver, Schematic Diagram (1 to 3500) . 0 0 00 0 0 0 0 95 42-B Receiver, Schematic Diagram (3501 to 9500) . . . . . . . . . . . 0 0 . 0 . 96 42-C Receiver, Schematic Diagram (9501 to 17,691) . . . . . . . . . 0 0. 97 42-D Receiver, Schematic Diagram (Over 17,691) . . . . . . . . . . . . . . . . . . 98 42-E Receiver, Schematic Diagram (Over 43,683) . . . . . . . . . 0 0 0 99 43-A Receiver, Connection Diagram (1 to 3500) . . . . 0 0 0 0 0 0 100 43-B Receiver, Connection Diagram (3501 to 9500) . . . . . . . . . 0 0 0 0 0 0 0 101 43-C Receiver, Connection Diagram (9501 to 17,691) . . . . . 0 000. 0 0 0 00 102 43-D Receiver, Connection Diagram (Over 17,691) . . . . . . . . . . . . 0 103 43-E Receiver, Connection Diagram (Over 43,683) . . . . . . . . . . . . . . . . . . . . . . . 104 44-A Transmitter, Schematic Diagram (1 to 3500) . . . . . . . . . . . . . . . . . . . . . . . . . . 105 44-B Transmitter, Schematic Diagram (3501 to 9500) . . . . . . . . . . . . . . . . . . . . . . . 106 44-C Transmitter, Schematic Diagram (9501 to 13,000) . . . . . . . . . . . . . . . . . . . . . 107 44-D Transmitter, Schematic Diagram (13,001 to 17,691) . . . . . . . . . . . . . . . . . . . . 108 44-E Transmitter, Schematic Diagram . (Over 17,691) . . . . . . . . . . . . . . . ; . . . . . . . 109 45-A Transmitter, Connection Diagram (1 to 9500) . . . . . . . . . . . . . . . . . . . . . . . . . . 110 45-B Transmitter, Connection Diagram (9501 to 12,000) . . . . . . . . . . . . . . . . . . . . . III 45-C Transmitter, Connection Diagram (12,001 to 13,000) . . . . . . . . . . . . . . . . . . 112 45-D Transmitter, Connection Diagram (13,001 to 17,691) . . . . . . . . . . . . . . . . . 113 45-E Transmitter, Connection Diagram (17,692 to 20,891) . . . . . . . . . . . . . . . . . . 114 45-F Transmitter, Connection Diagram (Over 20,891) . . . . . . . . . . . . . . . . . . . . . . . 115 46-A Cord CD-501-A, Connection Diagram . . . . 116 47-A Simplified Switching and Cording, Schematic Diagram . . . . 0 117 48-A Power Converter PE-104-A (Alternate) Schematic Diagram (Over 12,000). . . . . . 118 48-B Power Converter PE-104-A (Alternate) Connection Diagram (Over 12,000) . . . . . 119 49-A Power Unit PE-103-A, Schematic Diagram (1 to 4710) . . . . . . . . . . . . . . . . . . . . . . . . . 120 49-B Power Unit PE-103-A, Connection Diagram (1 to 4710) . . . . . . . . . . . . . . . . . . . . . . . . . . 121 50-A Generator GN-45-B, Schematic Diagram . 122 50-B Generator GN-45 . A, Schematic Diagram . 123 51-A Generator GN-45-B, Connection Diagram . 124 51-B Generator GN-45-A, Connection Diagram . 125 DESTRUCTION NOTICE WHY -To prevent the enemy from using or salvagillg this equipment for his benefit. WHEN-When ordered by your commander. HOW -1. Smash -Use sledges, axes, handaxes, pickaxes, hammers, crowbars, heavy tools, etc. 2. Cut -Use axes, handaxes, machetes, etc. 3. Burn -Use gasoline, kerosene, oil, flame throwers, incendiary grenades, etc. 4. Explosives-Use firearms, grenades, TNT, etc. 5. Disposal -Bury in slit trenches, fox holes, other holes. Throw in streams. Scatter. USE ANYTHING IMMEDIATELY AVAILABLE FOR DESTRUCTION OF THIS EQUIPMENT WHAT-I. Smash -All vacuum tubes, coils, switches, capacitors, microphones, headsets, insulators, mast sections, dynamotor, batteries, key, remote control unit, frame, cable connectors, legs, cranks. 2. Cut -Coils and cables, antenna and counterpoise wire, and guys. 3. Burn -Canvas bags, technical manuals, and all inflammable parts of equipment. 4,. Bury or scatter-Any or all of above pieces after destroying them. DESTROY EVERYTHING SAFETY NOTICE THIS EQUIPMENT CONTAINS VOLTAGES HIGH ENOUGH TO EN DANGER LIFE. EVERY REASONABLE SAFETY MEASURE HAS BEEN INCORPORATED INTO THE DESIGN TO PROTECT OPERATING PERSONNEL. BEFORE REMOVING THE TRANSMITTER-RECEIVER UNIT FROM ITS CASE, CHANGING TUBES OR MAIING INTERNAL ADJUST MENTS TO ANY ONE OF THE UNITS, THE POWER SUPPLY MUST BE COMPLETELY DISCONNECTED. WHEN THE EQUIPMENT IS STORED OR IS NOT TO BE USED FOR ANY LENGTH OF TIME, THROW THE CIRCUIT BREAKERS TO THE OFF POSITION. v PAR. I Recei-ver BC-654-A .,-.- _ COInpartment for Power Converter PE104-A or Battery BA-43 Transmitter BC .654-A - Cord CD-50l-A -. Frame FM-41-A Power lTnit PE . I03-A Battery Cables SCR-284-A FIG. 1. RADIO SET SCR-284-A VI TM 11-275 TM 11-275 SECTION I. 1. General a. Radio Set SCR-284-A is a combined receiver and transmitter, for operation in a vehicle or on the ground. (1) For use in a vehicle, cotton-web straps, D-ring loops and mounting brackets are included for convenient installation. (2) For ground operation, the necessary components may be grouped for a three man load. (3) Remote Control Unit RM-29-(*) provides flex ible control over a two wire telephone line in various combinations. b. Receiver:- (1) Frequency range: Continuous 3800 to 5800 kc. (2) Beat frequency oscillator: On fixed frequency of 455 kc. PARS. 1-2 DESCRIPTION (3) Output: 100 mw. into two 8000 ohm headsets in parallel. c. Transmitler:- (1) Frequency range: Continuous 3800 to 5800 kc. (2) Calibration: Every 10 kc. with crystal oscilla tor check every 200 kc. (3) Power output: 17 watts into vehicle antenna. 2. List of Com.ponent Parts a. When the Radio Set SCR-284-A is used in the field for ground operation, the following are the com ponents, grouped as a three man load. NOTE: The symbol (*) following a model number indicates that information given applies to all models. Quantity Description Dimensions Unit Weight (Lbs.) LOAD No. 1 1 Radio Receiver and Transmitter BC- 654-A includes Crystal Unit installed in socket, and Key J-48-A, but not Battery BA-43 . . . . . . . . . . . . . . . . . . . . . 18 x I4 x 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 .75 LOAD No. 2 1 Case CS-41 containing 1 Generator GN-45-(*) . . . . . . . . . . . . . . . 9 x 67.4 x 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 .44 1 Roll BG-58, canvas, for carrying mast sections and generator legs . . . . . . . . 30 long, 8 diam. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 .40 Items carried in Roll BG-58: 2 Cranks GC-7 .35 lb. each. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 1 Leg LG-2-A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 .25 2 Legs LG-3 1 lb. each. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 . 00 4 Legs LG-13-A .30 lb. each . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 .20 1 Insulator IN-I06-A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75 1 each Mast Sections MS-49 to MS-56 (incl.) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 .45 15 ft. Wire W-142. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 TOTAL 40 . 69 LOAD No. 3 1 Bag BG-I02-A, canvas . . . . . . . . . . . . . . 14Y2 x 137.4 x 97.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 .25 Items carried in Bag BG-I02-A: 2 Batteries BA-43 4.75 lbs. each . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 . 50 2 Headsets HS-30-(*) 1.18 lbs. each. See Note l. . . . 2 .36 1 Cord CD-SOl-A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 .25 1 Counterpoise CP-12 . 1 .67 1 Counterpoise CP-13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 .50 1 Reel RL-28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 1 Reel RL-29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75 1 Microphone T-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75 1 Guy GY-11 . . . . . . .