Bulletins

Rockwell-Collins Incorporated, 400 Collins Road NE, Cedar Rapids, Iowa, 52498, grants to the Collins Radio Association the non-exclusive, worldwide, royalty free license to reproduce and disseminate, in electronic and written format, any Collins Service Bulletins for Collins amateur radio products.

The Collins Radio Association desires to support the preservation and use of Collins amateur radio equipment by providing these Collins service bulletins, which will contribute to the continued use and enjoyment of Collins amateur radio equipmet, at no cost or obligation to CRA members and the general public for their own personal use, only.

Please note that these documents contain Rockwell Collins, Inc. copyrighted information and are used with permission. The Collins Radio logos contained herein are Trademarks of Rockwell Collns Inc. and are also used with permission.


Collins Service Bulletins for KWM-1:

SB1 (9-12-58) Improvement in Calibrator Operation, Spurious Outputs of KWM-1, Transient i Speaker when switching from Receiver to Transmit, Hum in Speaker when AF Gain Control is Advanced in CW Operation, Tweats in Audio Output cased by DC Power Supply    Page 1  Page 2   Page 3   Page 4    Page 5    Page 6   Page 7   Page 8

Collins Service Bulletins for KWM-2:

 SB2 (10-01-60) Add Vox Relay Time Constant Control  Page 1 Page 2  Page 3 Page 4

SB3 (01-10-71) Correlation Between Frequencies on Different Bands Page 1 Page 2 Page 3
SB4 (9-2-60) Improvement of ALC Action and Elimination of ALC Overshoot Page 1 Page 2
SB5 (11-23-60) To Improve Transmit-Receive Exciter Tuning Coincidence Page 1 Page 2 Page 3 Page 4
SB6 (1-11-62) To Eliminate Delay in Operation when Switching from Transmit to Receive Function
Page 1 Page 2
SB7 (1-2-70) Plug In Relays Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8
SB8 (1-8-70) Eliminate AGC overshoot on noise pulses and provide dual time-constant action, Change source of delay bias to the AGC rectifier, Add delayed-decay (hang) AGC to the rf amplifier Page 1 Page 2 Page 3 Page 4 Page 5 Page 6
SB9 (15-4-73) Convert KWM-2 to KWM-2A Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7
SB10 (15-04-74) Eliminate VHF parasitic oscillations in tone oscillator, V2B Page 1 Page 2


Collins Service Bulletins for 30L-1:

 SB1 (21-8-61) Wiring change required before conversion from 115VAC to 230VAC  Page 1 Page 2 Page 3
SB2 (2-20-62) Backward Deflection of ALC meter Page 1 Page 2
SB3 (4-2-62) To lower operating temperature of PA tubes Page 1 Page 2 Page 3
SB4 (11-15-77) Operation from 230V AC Power Source Page 1 Page 2


Collins Service Bulletins for 30S-1:

SB1 (6-21-61) To increase operating life of PA tube   Page 1   Page 2   Page 3  Page 4
SB2 (1-11-69) Prevent Intermittent dropout of plate overload relay Page 1 Page 2
SB3 (1-11-69) Reduce excessive ALC control Page 1 Page 2 Page 3


Collins Service Bulletins for 32S-1/2:

SB1 (6-30-59) Improve VOX operation   Page 1   Page 2
SB2 (4-1-60) Improve carrier suppression   Page 1 Page 2 Page 3 Page 4 Page 5
SB3 (8-8-60) Add VOX relay time constant control   Page 1 Page 2 Page 3 Page 4
SB4 (2-20-62) To improve CW Operation    Page 1 Page 2 Page 3 Page 4


Collins Service Bulletins for 32S-3/3A:

SB1 (8-8-57) Improve VOX circuit to eliminate intermittent dropout, and improve operation of first audio amplifier   Page 1   Page 2   Page 3   Page 4
SB2 (21-9-67) Removal of audio distortion   Page 1   Page 2
SB7 (15-10-75) Convert 32S-3 to 32S-3A   Page 1  Page 2  Page 3  Page 4  Page 5  Page 6  Page 7  Page 8


Collins Service Bulletins for 51S1/55G1

SB1 (5-15-63) Reduced hum in audio output with use of 28-volt DC power supply   Page 1   Page 2
SB2 (6-15-79) Replacment of transformers T14 and T15 with mechanical filter  Page 1   Page 2   Page 3 Page 4    Page 5   Page 6
SB3 (8-11-64) Improve sensitivity of lower bands Page 1   Page 2
SB4 (8-9-65) Addition of dial lock assembly   Page 1   Page 2
SB5 (1-4-70) Convert 51S-1/1F to 51S-1A/1AF   Page 1   Page 2   Page 3   Page 4   Page 5  Page 6   Page 7
SB6 (1-9-71) Provision for high-speed receiver muting and recovery   Page 1   Page 2   Page 3   Page 4    Page 5
SB7 (1-1-72) Reduce 500-Khz Spurious Response   Page 1   Page 2   Page 3
SB1 55G1 (25 Jul 69) Increase current handling capability of 115V line fuse   Page 1    Page 2


Collins Service Bulletins for 62S-1:

SB1 (2-28-64) Improvement of operation of ALC circuit   Page 1   Page 2   Page 3


Collins Service Bulletins for 75S-3/3A:

SB1 (3-9-62) To eliminate BFO parasitic oscillations   Page 1   Page 2   Page 3
SB2 (5-10-62) To minimize background hum level    Page 1    Page 2


Collins Service Bulletins for 75S-3B/3C:

SB1 (2-28-67) Improved performance   Page 1Page 2   Page 3   Page 4   Page 5   Page 6   Page 7   Page 8   Page 9    Page 10   Page 11   Page 12   Page 13   Page 14   Page 15
SB2 (8-15-68) Second Mixer Plate Circuit Improvement  Page 1  Page 2  Page 3  Page 4  Page 5  Page 6  Page 7   Page 8   Page 9
SB3 (6-15-72) Convert 75S-3B to 75S-3C  Page 1  Page 2  Page 3  Page 4  Page 5  Page 6  Page 7


Collins Service Bulletins for 516E/F-1/2:

SB1 (9-12-58) 516E1 Modification for use with positive ground   Page 1   Page 2
SB1 (22-Feb-71) 516E2 Add bleeder resistor to +260-VDC line to improve safety features     Page 1     Page 2    Page 3


Collins Service Bulletins for PM2:

SB1 (17 Apr 63) Extension of design specifications for input voltage limits    Page 1   Page 2   Page 3   Page 4   Page 5   Page 6


Collins Service Information Letters (SIL):

SIL 75S-1, 32S-1, KWM-2 (2 Feb 60) VFO Oscillator Drift Page 1   Page 2

SIL KWM2 (15 Nov 60) Servicing Information Page 1 Page 2

SIL 1002 (1 Aug 60) for KWM-2, KWM-2A – Audio Squeal in Transmit When AF GAIN Control is Advanced Page 1

SIL 1005 (23 Dec 60) for KWM-2/2A, 75S-1/2, 30S-1, 136B-2 – Audio Instability In Calibrate Function, Excessive Hum On Carrier, Meter Calibration Resistor, T2 and L4 Same Part Number Page 1 Page 2

SIL 1006 (5 May 61) for KWM-2, KWM-2A – Audio Squeal After Transmitting, Burning or Pitting of Relay Contacts, 3.5Mhz Transmitting Spurious, R.F. Transient Page 1 Page 2

SIL 1007 (12 May 61) for 75S-1,-2, 32S-1,-2, KWM-2,-2A, 312B-5 – Main Tuning Dial Assembly and Repair, PTO to Tuning Dial Adjustment Page 1

SIL 1009 (3 Jul 62) for KWM-2, KWM-2A; Transmitters 32S-1, 32S-2 – Low Crystal Calibrate Injection Voltage On 10 Meters, Extend Range of Receiver Gain Adjustment Control, Increase Accuracy of “S” Meter and Extend Range of Zeroing Potentiometer, Transmitter Instability Page 1 Page 2 Page 3

SIL 1011 (15 Apr 61) Description of S-Line and KWM-2 Dial Assemblies and their Alignment Procedures, including Pictorals 1 and 2 Page 1 Page 2 Page 3 Page 4 Page 5 Page 6     Pictoral 1     Pictoral 2

SIL 1013 (18 Mar 64) for KWM2/KWM-2A Noise Activation of AGC System Page 1

SIL 1016 (10-12-65) for KWM2/KWM-2A Crystal Calibration, “Yelp” problem, Reduce Low-Frequency Spurious, High Frequency Tweets, Eliminate 0.455-KC Signal Bypassing Transmit Mixer, Improve Carrier Balance    Page 1    Page 2   Page 3   Page 4

SIL 2-75 (15 Oct 75) for KWM-2/2A, 32S-1/2/3/3A, 75S-1/2/3/3A/3B/3C Extended Operating Range Page 1   Page 2

Field Service Activity Report 44-63-1 (11-3-63) for KWT-6, KWM-2A     Page 1   Page 2

Field Service Activity Report 28-64-1 (7-12-64) for KWM-2A, 30S1, URG, MW-503    Page 1

Field Service Activity Report 29-64-1 (7-19-64) for KWM-2A, 30S-1, URG, MW503    Page 1

Field Service Activity Report 32-64-1 (7-19-64) for SSB     Page 1

Field Service Activity Report 32-64-1 (8-23-64) for SSB     Page 1