[R-1000]   [TS-120S]   [TS-430S][AT-250]   [TS-450S]   [TS-660]   [TM-732A]   [TW-4000A]   [TW-4100A]  
Hi-res schematics and new or redrawn figures ©2008 WB4KDI Dave J. Barnes.
Some figures from original Kenwood USA Word documents.

Mods for several models

[Adjustable Sidetone Pitch]
*[Replace the battery with a Super Cap]
*[Replace those lamps with super bright LEDs]

R-1000


[HELP! I just got a R-1000.]
[Polishing Kenwood's R-1000] from 73 Magazine, March 1982, p. 34-36

Kenwood Service Bulletins

[SB-805 - Muting]
[SB-813 - AGC, AM bandwidth changes]
[SB-823 - RF attenuator 10 dB step option]

TH-K20A


TS-120S

    
Yellow LEDs instead of lamps! ===^
[HELP! I just got a TS-120.]
[10 Hz Display]
[Other Modifications by WB4KDI]
[Phone Patch] from 73 Magazine, February 1981, p. 50

Kenwood Service Bulletins

[SB-037 - VOX Operation Pick-up Time]
[SB-038 - Final Amplifier Replacement]
[SB-048 - Hum (RF Feedback) in SSB TX]
[SB-051 - Final Protection]
[SB-060 - Repair Notes]
[SB-816 - Band Pass Filter Change]
[SB-827 - VFO Stability]
[SB-831 - Ant Input Transformer Replacement]
[SB-832 - Full CW Output in SSB Mode]
[SB-844 - TX Oscillation (Supercedes SB-821)]

DFC-230
[DFC-230 Owners Manual]

[Schematic]
TS-430S


Yellow LED instead of lamp!
[HELP! I just got a TS-430.]

Kenwood Service Bulletins

[SB-865 - 500 kHz Heterodyne]
[SB-882 - Notch Control]
[SB-883 - AM Wide/Narrow Filter Selection]
[SB-885 - Receiver Internal Beat]
[SB-887 - Noise Blanker Improvements]
[SB-888 - Intermittent PLL Unlock in FM/AM]
[SB-895 - PLL Unlock at High Temperatures (Revision)]
[SB-902 - Low / Intermittent Receive]

AT-250
[AT-250 Owners Manual]

[Hi-Res Schematic]

TS-450S/TS-690S

    
FCC-ID: ALHTS-450 / ALHTS-690
[Function Programming Summary]
[HELP! I just got a TS-450/690.]
[Other Modifications by WB4KDI]

Kenwood Service Bulletins

[ASB-995 - Calibration Cable Change]
[ASB-1002 - Distorted TX with TNC]
[ASB-1004 - TX Frequency Response]
[ASB-1032 - Low Mic Gain w/DSP-100]
[ASB-1036/APU-0017 - Parts Change (Driver Transistor)]
[APU-0018 - Rotary Encoder Change]
[ASB-1059 - Noisy Encoder]

TS-660


FCC-ID: ALH9TKTS-660 (Invalid!)
[HELP! I just got a TS-660.]

Kenwood Service Bulletins

[SB-856 - Microprocessor Latchup]

TM-732A

FCC-ID: ALHTM-732A
[Programming Quick Reference]
[Additional Features and Modifications]

Kenwood Service Bulletins

[ASB-996 - 2 Meter Transmit Interference on 70 CM]
[ASB-1005 - Change in Chip Fuse Rating]
[ASB-1011 - Low Cross-band Repeat Audio]
[ASB-1014 - Noise at Squelch ON/OFF]
[ASB-1023 - S-Meter Squelch Scan Stop Improvement]
[ASB-1027 - Protection of Q201 in 430 MHz Unit]
[ASB-1051 - Control PC Board B+ Foil Damage]
[ASB-1056 - APC Circuit Improvement]

TW-4000A

FCC-ID: ALH9TKTW-4000A
[CTCSS Settings]

TW-4100A

FCC-ID: ALH9TKTW-4100A
Yellow LEDs instead of lamps!
[Frequency Modifications]
[MA-4000 Duplexer]

Kenwood Service Bulletins

[SB-926 - Repeater Stop Scan on the UHF Band]