KENWOOD SERVICE BULLETINS BY MODEL 11/09/89
MODEL SB # TITLE
AT-930 877 SERVICE NOTES
BS-8 41 ALIGNMENT WITH TS-180S
DG-1 19 NEW DISPLAY TUBE
DG-1 26 SERVICE NOTES
DG-1 53 STANDARD SERVICE
DG-5 25 REPAIR
DG-5 28 REPAIR NOTES
DG-5 29 THEORY OF OPERATION
DG-5 54 STANDARD SERVICE
DK-520 62 DG-5 USE WITH TS-511/TS-900/T/R-599
DS-2 842 REPLACEMENT FOR DS-1A
HMC-1 914 NOT TO BE USED WITH TH-205AT/TH-215A
MC-45 35 MODIFICATION FOR USE WITH TR-7400A
MC-46 852 DTMF OPERATION WITH OLDER EQUIPMENT
MC-55 953 CHANGE IN MIC ELEMENT (T91-0328-08)
PS-430 938 VOLTAGE INCREASE WITH TH-205/215
PS-50 916 IMPROVED VOLTAGE SURGE PROTECTION
QR-666 3 VFO STABILITY
R-1000 805 MUTING
R-1000 813 AGC AM BANDWIDTH CHANGES
R-1000 823 RF ATTENUATOR 10dB STEP OPTION
R-5000 919 NO FREQ CHANGE BY COMPUTER INTERFACE
R-599A/D 8 SERVICE NOTES
R-599A/D 31 REMOVING CB BAND
RC-10 922 HANG UP TIME/TIMEOUT TIMER SETTINGS
RC-10 927 ALTERNATOR NOISE
RM-76 33 FREQUENCY ERROR WITH TR-7600/7625
RM-76 59 BATTERY BACK-UP POWER
RM-76 802 MICROPROCESSOR FAILURE
SM-220 57 SHIELD INSTALLATION
SM-220 66 FEEDBACK FROM BS-8
SMC-25 864 MODIFICATION FOR USE WITH THE TR-
2400
T-599A/D 7 SERVICE NOTES
T-599D 6 CHAIN DRIVE MODIFICATION
T-599D 17 REDUCING 120Hz HUM
TH-205 945 SIGNAL TO NOISE RATIO IMPROVEMENT
TH-205/215 920 PROTECTION FUSE REPLACEMENT WITH
DIODE
TH-205/215 944 VOLUME/SQUELCH CONTROL IMPROVEMENT
TH-215/415 946 TX SIGNAL TO NOISE RATIO IMPROVEMENT
TH-25/45 932 W/TSU-6 TONE ALERT IMPROVEMENTS
TH-25/45 939 AUTOMATIC POWER OFF
TM-201/401 880 INCREASED TX AUDIO
TM-211/411 897 AF GAIN CONTROL PART CHANGE
TM-221A 933 NO TX IN HIGH POWER DUE TO VOLTAGE
DROP
TM-221A 934 FINAL MODULE HINTS
TM-2550 904 DCL CALL SIGN DATA
TM-2570 906 LOW TX POWER OUTPUT
TM-321A 935 LOSS OF TX AUDIO WITH MC-48B
TM-3530A 925 NOISY TRANSMIT
TM-411 892 LOW/NO RECEIVER SENSITIVITY
TM-721A 930 MICROCOMPUTER LOCK-UP
TM-721A 931 LOW/NO VHF TRANSMIT POWER
TM-721A 936 S-METER DEFLECTION DUE TO PULSE
NOISE
TM-721A 937 AF PA WHITE NOISE WITH SQUELCH ON
TR-2200A 11 ANTENNA ADAPTER
TR-2200A 22 SERVICE NOTES
TR-2400 58 TONE ENCODER RFI
TR-2400 807 OPTIONAL CHARGE INPUT PROTECTION
TR-2400 808 OFFSET FAILURE
TR-2400 809 UNWANTED NOISE: TONE OR BURST AT TX
TR-2400 810 DISPLAY OR KEYBOARD TROUBLE
TR-2400 811 RX LOW INTERMITTENT OR DISTORTED
TR-2400 814 UNLOCK
TR-2400 815 PULSE NOISE
TR-2400 818 SCRATCHY TX
TR-2400 819 VOLUME CONTROL REPLACEMENT
TR-2400 822 BATTERY CHARGER FAILURE
TR-2400 830 TX NOISE
TR-2500 858 RX IMD IMPROVEMENT
TR-2600A 901 PLL UNLOCK (TROUBLESHOOTING)
TR-2600A 903 PLL UNLOCK
TR-7200A 23 SERVICE NOTES
TR-7400A 10 FINAL UNIT ARCING
TR-7400A 18 SERVICE NOTES
TR-7400A 32 CHANGES IN PD UNIT
TR-7400A 34 METER LAMP LONGER LIFE
TR-7600/7625 39 ALTERNATOR WHINE
TR-7600/7625 45 AUDIO TONE ON TX
TR-7600/7625 50 OPTIONAL CERAMIC FILTER
TR-7600/7625 65 RF POWER MODULE RETURNS (OBSOLETE)
TR-7600/7625 806 MEMORY BATTERY BACK-UP
TR-7625 804 INTERMITTENT TX
TR-7625 820 FINAL MODULE REPLACEMENT
TR-7625 826 HYBRID AMPLIFIER MODULE SUBSTITUTION
TR-7730 854 TX FREQUENCY RESPONSE VOICE OR DTMF
TR-7800 828 TONE PAD CONVERSION FOR 4th COLUMN
FUNCTION
TR-7800 829 MEMORY LOSS SUPERSEDED BY SB-861
TR-7800 834 PULSE NOISE
TR-7800/7850 860 MEMORY CH. 7 INDICATOR ERRATIC
TR-7800/7850 861 MEMORY IMPROVEMENTS
TR-7800/9000 833 OPTIONAL CERAMIC FILTERS
TR-7850 846 RF LED METER (LOW READINGS)
TR-7930/7950 870 RX INTERFERENCE
TR-8300 16 ALIGNMENT
TR-8400 843 SUB-AUDIBLE ENCODER INSTALLATION
TR-8400 845 RX INTERNAL SPURIOUS SIGNALS
TR-8400 853 TX FREQ RESPONSE VOICE OR DTMF
TR-8400 855 TRANSMIT DELAY TIME
TR-9000 824 CW/SSB TX INSTABILITY
TR-9000 825 TX PULSE NOISE IN SSB
TR-9000 849 TRANSMITTER SIDEBAND CARRIER BALANCE
TR-9000 859 TEMPERATURE STABILITY IMPROVEMENT
TR-9130 871 LOW DRIVE LEVEL
TS-120S 37 VOX OPERATION PICK-UP TIME
TS-120S 38 FINAL TRANSISTOR REPLACEMENT
TS-120S 40 ANTENNA INPUT TRANSFORMER
REPLACEMENT
TS-120S 48 HUM IN SSB TX
TS-120S 51 FINAL PROTECTION
TS-120S 60 REPAIR NOTES
TS-120S 64 FULL CW OUTPUT IN SSB MODE (USE SB-
844)
TS-120S 801 TX OSCILLATION (USE SB-844)
TS-120S 816 BAND PASS FILTER CHANGE
TS-120S 827 VFO STABILITY
TS-120S 821 TX OSCILLATION (USE SB-844)
TS-120S 831 ANTENNA INPUT TRANSFORMER
REPLACEMENT
TS-120S 832 FULL CW OUTPUT IN SSB MODE (USE SB-
844)
TS-120S 844 TX OSCILLATION
TS-120S/180S 44 PHONE PATCH TERMINAL ADDITION
TS-140S 928 INTERMITTENT LOSS OF TRANSMIT POWER
TS-140S 929 MOMENTARY TX WHEN VOX IS TURNED ON
TS-180S 36 DFC HUM WITH PS-30
TS-180S 42 IF #2 OUTPUT LEVEL CHANGE
TS-180S 47 INCREASE OF RX AUDIO OUTPUT
TS-180S 55 LOW 40 MTR ALC
TS-180S 56 DFC
TS-180S 61 TROUBLE SHEET
TS-180S 67 DFC INSTABILITY
TS-180S 803 CW DELAY DURING VOX MEMORY OPERATION
TS-180S 817 USE WITH A LINEAR AMPLIFIER
TS-180S 839 VFO STABILITY
TS-180S 850 LOW PASS FILTER OPTIONAL CHANGES
TS-430S 865 500KHz HETERODYNE
TS-430S 882 NOTCH CONTROL
TS-430S 883 AM WIDE/NARROW FILTER SELECTION
TS-430S 885 RECEIVER INTERNAL BEAT
TS-430S 887 NOISE BLANKER IMPROVEMENTS
TS-430S 888 INTERMITTENT PLL UNLOCK IN FM/AM
TS-430S 891 PLL UNLOCK AT HIGH TEMP. (USE SB-
895)
TS-430S 895 PLL UNLOCK AT HIGH TEMPERATURES
TS-430S 902 LOW/INTERMITTENT RX
TS-440S 947 OPERATION WITH THE MC-85
TS-440S 948 NOTCH FILTER LOW FREQUENCY
IMPROVEMENTS
TS-440S 949 PROTECTING Q33
TS-440S 950 CASE SCREWS BINDING IN THE HEAT SINK
TS-440S 952 INTERMITTENT OPERATION (REMOVE
SOCKET)
TS-520 2 NOVICE OPERATION (75 WATTS)
TS-520 4 AM BROADCAST INTERFERENCE
TS-520 21 SERVICE NOTES
TS-520 63 IF OUTPUT FOR SM-220
TS-520(S) 46 CW FREQUENCY SHIFT
TS-520(S) 52 BS-5 SWEEP INTERFERENCE
TS-520S 43 -6VDC SUPPLY FAILURE
TS-520S/820S 812 CW FILTER SELECT CONTROL
TS-530S 848 LOW VOLTAGE SUPPLY OPTIONAL
IMPROVEMENTS
TS-530S 878 IF UNIT Q2-Q7 PROTECTION
TS-660 856 MICROPROCESSOR LATCH-UP
TS-700A 20 SERVICE NOTES
TS-700A 5 REPEATER MODIFICATION (EUROPE)
TS-700A 27 9 VOLT REGULATOR REPLACEMENT
TS-820 12 AUX BAND INSTALLATION (RX ONLY)
TS-820 13 RIT MODIFICATION
TS-820 14 MICROPHONE INPUT ATTENUATOR
TS-820S 9 SPEECH PROCESSOR ALIGNMENT
TS-820S 24 SERVICE NOTES
TS-820S 30 GENERAL ALIGNMENT PROCEDURES
TS-820S 954 TA7201P SUBSTITUTION PARTS KIT
TS-830S 837 OPERATION ON 240V AC
TS-830S 840 FREQUENCY SHIFT
TS-830S 847 LOW VOLTAGE SUPPLY OPTIONAL
IMPROVEMENTS
TS-830S 851 NOISE BLANKER OPTIONAL IMPROVEMENTS
TS-830S 857 TRANSMITTER "TALKBACK"
TS-930S 863 INCORRECT LINE VOLTAGE SETTING
(OBSOLETE)
TS-930S 866 CW HETERODYNE TONE
TS-930S 867 SSB TX TONE QUALITY
TS-930S 868 LOW RX SENSITIVITY
TS-930S 869 PLL UNLOCK
TS-930S 872 CW PITCH TONE SHIFT
TS-930S 873 CW VBT
TS-930S 874 RF FEEDBACK
TS-930S 875 RX AUDIO OSCILLATION
TS-930S 876 RF FEEDBACK INTO MIC CIRCUIT
TS-930S 879 ALC LEVEL DRIFT 28 MHz CW
TS-930S 881 POWER SUPPLY SURGE PROTECTION
TS-930S 884 15 MTR INTERNAL BEAT NOTE
TS-930S 886 INTERMITTENT TX POWER OUTPUT
TS-930S 893 NOISY POWER SUPPLY FAN
TS-940S 896 LCD CLOCK DISPLAY ERRATIC OPERATION
TS-940S 900 PLL UNLOCK
TS-940S 907 ANTENNA TUNER RELAYS
TS-940S 908 PLL UNLOCK
TS-940S 909 AVR UNIT CAPACITOR CHANGE
TS-940S 910 AGC CIRCUIT IMPROVEMENTS
TS-940S 912 TRANSMITTER HUM IN SSB
TS-940S 913 SIGNAL TO NOISE RATIO IMPROVEMENT
TS-940S 917 VCO CARRIER TO NOISE RATIO
IMPROVEMENT
TS-940S 918 SQUELCH SWITCHING NOISE
TS-940S 921 SSB TALK POWER IMPROVEMENT
TS-940S 951 ERRATIC DISPLAY (REMOVE SOCKET)
TW-4100A 926 REPEATER STOP SCAN ON THE UHF BAND
VFO-120 862 DIAL LAMP SWITCHING CIRCUIT
VFO-230 838 OPERATION ON 240V AC
VOX-3 15 SENSITIVITY AND DELAY
49 UHF/VHF OPTIONAL FILTER LIST
905 COAX CABLE W/PLUG LIST
941 SERVICE MANUAL RX SECTION LEVEL
DIAGRAMS
942 SERVICE MANUAL TX SECTION LEVEL
DIAGRAMS