Kenwood Amateur Radio Service Bulletins By Model Number
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pages in document!
AT-50 AT-50 BLOWS ACCESSORY FUSE IN
TS-50
AT-50 BLOWS ACCY FUSE IN TS-50
more
AT-50 MECHANICAL STABILITY OF CASE
AT-930 SERVICE NOTES MORE
BS-5 SM-220/BS-5 SWEEP INTERFERENCE
BS-8 ALIGNMENT WITH TS-180S/SM220
MORE
DG-1 SERVICE NOTE / BAD SOLDER JOINTS
DG-1 SERVICE NOTES (PC BOARD SOLDER)
MORE
DG-5 REPAIR OF RCA PLUGS/JACKS
DG-5 REPAIR NOTES
MORE
DG-5 THEORY OF OPERATION
MORE
DG-5 SERVICE NOTES (PC BOARD SOLDER)
MORE
DG-5 USE WITH TS-511/TS-900/T/R-599
MORE
MORE
DK-520 USE
WITH TS-511/TS-900/T/R-599 MORE
MORE
DRU-2 ERRATIC PLAYBACK/MEMORY LOSS
MORE
DS-2 REPLACEMENT FOR DS-1A IN
TS820/TS520
DSP-100 6
PIN CABLE CHANGE
HMC-1 NOT TO BE USED WITH
TH-205AT/TH-215A
MC-44DM INTERMITTENT
AUDIO
MC-44DM INCREASE
IN AUDIO LEVEL
MC-45 MODIFICATION FOR USE WITH
TR-7400A MORE
MC-46 DTMF OPERATION WITH OLDER
EQUIPMENT
MC-48 MIC ELEMENT CHANGE /INSTALLATION
MC-55 CHANGE IN MIC ELEMENT
(T91-0328-08)
QR-666 VFO
STABILITY IN SWL RECEIVER
PB-2/PB-12 BATTERY CURRENT
LIMITING RESISTOR FAILURE
PS-430 VOLTAGE INCREASE WITH TH-205/215
MORE
PS-50 AVR FAILURE /IMPROVED SURGE
PROTECTION
R-599A/D SERVICE
NOTES
R-599A/D REMOVING
CB BAND
R-1000 AGC, AM BANDWIDTH CHANGES
MORE
R-1000 RF ATTENUATOR 10 DB STEP OPTION
R-1000 MUTING
OPERATION - OPS MANUAL UPDATE
R-5000 NO
FREQUENCY CHANGE THROUGH COMPUTER
RC-10 HANG UP TIME/TIMEOUT TIMER
SETTINGS/XBAND RPT MORE
RC-10 ALTERNATOR NOISE IN MIC CIRCUIT
RM-76 FREQUENCY ERROR WITH TR-7600/7625
RM-76 BATTERY BACK-UP POWER
RM-76 MICROPROCESSOR FAILURE
SM-220 ALIGNMENT
WITH TS-180S/SM220 MORE
SM-220 SM-220/BS-5
SWEEP INTERFERENCE
SM-220 SHIELD
INSTALLATION/SWEEP INTERFERENCE
SM-220 FEEDBACK
FROM BS-8
SM-230 BANDSCOPE ATTENUATION MOD
MORE
SM-230 RTTY
CROSS PATTERN MODIFICATION
SMC-25 MODIFICATION FOR USE WITH THE
TR-2400 MORE
SMC-34 DISTORTED/MUFFLED AUDIO
MORE
T-599A/D SERVICE
NOTES
T-599D REDUCING
120HZ HUM
TH-22AT MEMORY
LOSS WHEN BATTERY RUNS DOWN
TH-25A TSU-6 ERRATIC TONE ALERT FUNCTION
TH-25A DISABLE AUTOMATIC POWER OFF
FUNCTION MORE
TH-25AT KEYPAD
OVERLAY REPLACEMENT
TH-26A INTERNAL BIRDIES
MORE
MORE
TH-27A LOW
TX POWER WITH TOSHIBA MODULES
TH-28A DIFFICULT
BATT. INSERTION
TH-28A CTCSS
TONE ERROR - 131.8,136.5,173.8 HZ
TH-42AT MEMORY
LOSS WHEN BATTERY RUNS DOWN
TH-45A TSU-6 ERRATIC TONE ALERT FUNCTION
TH-45A DISABLE AUTOMATIC POWER OFF
FUNCTION MORE
TH-45AT KEYPAD
OVERLAY REPLACEMENT
TH-48A DIFFICULT
BATT. INSERTION
TH-48A CTCSS
TONE ERROR - 131.8,136.5,173.8 HZ
TH-48A MICRO
CHANGE - DISABLE 800 MHZ RECEIVE
TH-75A INTERMITTENT MEMORY LOSS MORE MORE MORE MORE
TH-75A NO
TX ON VHF WHEN IN VEHICLE
TH-77A MEMORY
LOSS WITH LOW BATTERY VOLTAGE MORE
TH-78A CLONE FAILURE W/ME-1 MORE
TH-78A LEFT
ENCODER INOPERATIVE
TH-78A CALL
CH. TONE FREQ PROBLEM WITH TSU-7
TH-78A DIFFICULT
BATT. INSERTION
TH-78A MICRO
CHANGE - DISABLE 800 MHZ RECEIVE
TH-78A IMD IMPROVEMENT MORE
TH-205A PROTECTION
FUSE REPLACEMENT WITH DIODE
TH-205A VOLUME/SQUELCH
CONTROL IMPROVEMENTS/BRACKET MORE
TH-205A RCV
SIGNAL TO NOISE RATIO IMPROVEMENTS MORE
TH-205A NEW PTT
KNOB INSTALLATION
TH-215A PROTECTION
FUSE REPLACEMENT WITH DIODE
TH-215A VOLUME/SQUELCH
CONTROL IMPROVEMENTS/BRACKET MORE
TH-215A TX SIGNAL TO
NOISE RATIO IMPROVEMENT MORE
TH-215A NEW PTT
KNOB INSTALLATION
TH-315A NEW PTT
KNOB INSTALLATION
TH-415A VOLUME/SQUELCH
CONTROL IMPROVEMENTS/BRACKET MORE
TH-415A TX SIGNAL TO
NOISE RATIO IMPROVEMENT MORE
TH-415A NEW PTT
KNOB INSTALLATION
TM-201 INCREASED
TX AUDIO / MIC GAIN
TM-221A NO TX IN
HIGH POWER DUE TO VOLTAGE DROP
TM-221A FINAL
MODULE/LOW POWER OUTPUT HINTS
TM-231A INTERMITTENT
MEMORY LOSS MORE
TM-321A LOSS OF TX
AUDIO WITH MC-48B
TM-401 INCREASED
TX AUDIO / MIC GAIN
TM-411 MICRO
CHANGE - DISABLE 800 MHZ RECEIVE
TM-455A CHANGE IN PIN
DIODE
TM-531A 20 MHZ OFFSET
MODIFICATION MORE
TM-631A MEMORY LOSS
MORE
MORE
MORE MORE MORE MORE MORE MORE
TM-631A 144MHZ FINAL
BOARD CHANGE
TM-642A MICRO
CHANGE - DISBALE 800 MHZ RECEIVE
TM-642A MICRO CHANGE -
SUPERCEDES ASB-1033
TM-701A INTERMITTENT
MEMORY LOSS
MORE
TM-721A MICROCOMPUTER
LOCK-UP
MORE
TM-721A LOW/NO VHF
TRANSMIT POWER
TM-721A S-METER
DEFLECTION DUE TO PULSE NOISE MORE
TM-721A AF PA WHITE
NOISE WITH UNIT SQULCHED MORE MORE
TM-731A MEMORY LOSS
MORE
MORE MORE MORE MORE MORE MORE MORE MORE
TM-731A 144MHZ FINAL
BOARD CHANGE MORE
TM-732A 440 RECEIVE
INTERFERENCE FROM 2 METER XMIT
TM-732A CHANGE IN VALUE
OF CHIP FUSE
TM-732A LOW CROSS-BAND
REPEAT AUDIO
MORE
TM-732A NOISE AT SQULECH
ON/OFF ON OTHER BAND
TM-732A S-METER SQUELCH
SCAN IMPROVEMENT
TM-732A CONTROL PCB FOIL
DAMAGE
TM-732A PROT OF Q201
(FIRST RF AMP) 440 SIDE
TM-732A APC CIRCUIT
MODIFICATION MORE
TM-733A PL TONE
DISTORTION/AUDIBLE MORE
TM-733A PL TONE BLEED
THRU TO SPEAKER
MORE
TM-742A 28MHZ/50MHZ R/C
XMIT FAILURE
TM-742A MICRO LOCKUP
WHEN IN REMOTE OPERATION
TM-742A MICRO CHANGE -
DISBALE 800 MHZ RECEIVE
TM-742A MICRO CHANGE -
SUPERCEDES ASB-1033
TM-941A BPF ALIGNMENT
TOOL
TM-942A 28MHZ/50MHZ R/C
XMIT FAILURE
TM-942A MICRO LOCKUP
WHEN IN REMOTE OPERATION
TM-942A MICRO CHANGE -
DISBALE 800 MHZ RECEIVE
TM-2550 DCL CALL
SIGN DATA LOSS
TM-2570 LOW TX
POWER OUTPUT WITH GOOD VSWR
TM-3530A NOISY TRANSMIT AFTER
WARMUP MORE
TR-2200A ANTENNA ADAPTER
TR-2200A SERVICE NOTES
TR-2400 TONE
ENCODER RFI/MOTORBOATING
TR-2400 OPTIONAL
CHARGE INPUT PROTECTION
TR-2400 OFFSET
FAILURE
TR-2400 UNWANTED
NOISE: TONE OR BURST AT TX
TR-2400 DISPLAY
OR KEYBOARD TROUBLE
TR-2400 RX
LOW, INTERMITTENT, OR DISTORTED
TR-2400 PLL
UNLOCK / LOW CRYSTAL ACTIVITY
TR-2400 PULSE
NOISE IN RECEIVE OR TRANSMIT
TR-2400 SCRATCHY
TX AUDIO
TR-2400 VOLUME
CONTROL REPLACEMENT - PRECAUTIONS
TR-2400 BATTERY
CHARGER FAILURE / REPAIR
TR-2400 EXCESSIVE
BACKGROUND NOISE ON XMIT
TR-2500 RX
IMD IMPROVEMENT
TR-2600A PLL UNLOCK
(TROUBLESHOOTING)
TR-2600A PLL UNLOCK
CAUSED BY OSC FAILURE
TR-7200A SERVICE NOTES
TR-7400A FINAL UNIT
ARCING
TR-7400A VARIOUS SERVICE
NOTES
TR-7400A CHANGES IN PD
UNIT OF IC'S
TR-7400A METER LAMP
LONGER LIFE
TR-7400A MODIFICATION
FOR USE WITH TR-7400A
TR-7600 ALTERNATOR
WHINE
TR-7600 AUDIO TONE
ON TX
TR-7600 OPTIONAL CERAMIC
FILTER
TR-7600 RF POWER
MODULE RETURNS (OBSOLETE)
TR-7600 MEMORY
BATTERY BACK-UP
TR-7625 ALTERNATOR WHINE
TR-7625 AUDIO TONE ON TX
TR-7625 OPTIONAL CERAMIC
FILTER
TR-7625 RF POWER MODULE
RETURNS (OBSOLETE)
TR-7625 INTERMITTENT TX
TR-7625 MEMORY BATTERY
BACK-UP
TR-7625 FINAL MODULE
REPLACEMENT (USE SB-826)
TR-7625 HYBRID
AMPLIFIER MODULE SUBSTITUTION
TR-7730 TRANSMITTER
FREQUENCY RESPONSE VOICE AND DTMF
TR-7800 TONE PAD
CONVERSION FOR 4TH COLUMN (ABCD)
TR-7800 INTERMITTANT
LOSS OF MEMORY
TR-7800 OPTIONAL
FILTERS TO IMPROVE SELECTIVITY
TR-7800 PULSE
NOISE AND SPKR BUZZ DURING XMIT
TR-7800 DISPLAY
FAILURE CAUSED BY FAILURE OF CLOCK
TR-7800 CONTINUOUS
CHARGE FOR INTERNAL BATTERIES
TR-7800 MEMORY CH.
7 INDICATOR ERRATIC
TR-7800 MEMORY
RETENTION IMPROVEMENTS
TR-7850 RF LED
METER DISPLAYS LOW READING
TR-7850 MEMORY CH.
7 INDICATOR ERRATIC
TR-7850 MEMORY
RETENTION IMPROVEMENTS
TR-7930 RX
INTERFERENCE FROM FM/TV BROADCAST
TR-7950 RX
INTERFERENCE FROM FM/TV BROADCAST
TR-8300 RECIEVER/TRANSMITTER
ALIGNMENT
TR-8400 SUB-AUDIBLE
ENCODER INSTALLATION
TR-8400 RX
INTERNAL SPURIOUS SIGNALS
TR-8400 TRANSMITTER
FREQUENCY RESPONSE VOICE AND DTMF
TR-8400 TRANSMIT/RECEIVE
SWITCH TIME / PLL LOCKUP
TR-9000 CW/SSB TX
INSTABILITY / FM'ING / CHIRP ON CW
TR-9000 TX PULSE
NOISE IN SSB TRANSMISSION
TR-9000 OPTIONAL
FILTERS TO IMPROVE SELECTIVITY
TR-9000 STABILITY
IMPROVEMENT / PLL UNLOCK
TR-9000 XMIT
SIDEBAND DISTORTION / CARRIER BALANCE
TR-9130 LOW DRIVE
LEVEL / LOW OUTPUT POWER
TS-50S LITHIUM
BATT. REPLACMENT CAUTION MORE
TS-50S "HELLO"
DISPLAYED DURING TRANSMIT
TS-50S ANTENNA
LEAD WIRE CONNECTION
TS-50S MECHANICAL
NOISE FROM FINAL UNIT
TS-120S VOX
OPERATION PICK-UP TIME
TS-120S FINAL
TRANSISTOR REPLACEMENT
TS-120S ANTENNA
INPUT TRANSFORMER REPLACEMENT
TS-120S PHONE PATCH
TERMINAL ADDITION
TS-120S HUM IN SSB
TX
TS-120S FINAL
PROTECTION
TS-120S REPAIR
NOTES
TS-120S FULL CW
OUTPUT IN SSB MODE (USE SB-944)
TS-120S TX
OSCILLATION (USE SB-844)
TS-120S BAND PASS
FILTER CHANGE - IMPROVE SELECTIVITY
TS-120S TX
OSCILLATION (SEE ASB-844)
TS-120S VFO
INSTABILITY AND DRIFT
TS-120S ANT INPUT
TRANSFORMER REPLACEMENT
TS-120S FULL CW
OUTPUT IN SSB MODE
TS-120S TX
OSCILLATION ESPECIALLY ON 10-15-20 METERS
TS-140S INTERMITTENT
LOSS OF TRANSMIT POWER
TS-140S MOMENTARY
TRANSMISSION WHEN VOX IS TURNED ON MORE
TS-180S ALIGNMENT
WITH TS-180S/SM220
TS-180S IF #2 OUTPUT
LEVEL FOR SM220 OPERATION
TS-180S PHONE
PATCH TERMINAL ADDITION
TS-180S INCREASE
OF RX AUDIO OUTPUT
TS-180S HUM WITH
PS-30/ERRATIC DFC
TS-180S ALC LOSS
OR REDUCTION ON 40 METERS
TS-180S DFC/HUM/INTERMITTANT
FREQ STABILITY
TS-180S TROUBLE
SHEET/REPAIR NOTES
TS-180S DFC
INSTABILITY
TS-180S CW DELAED
KEYING DURING CW VOX OPERATION
TS-180S LINEAR AMPLIFIER
OPERATION / SWITCHING TIMES
TS-180S VFO INSTABILITY
/ DRIFT IMPROVEMENT
TS-180S ALC LEVEL
IMPROVEMENT / LPF CHANGES
TS-430S 500 KHZ
HETERODYNE
TS-430S NOTCH
CONTROL/BETTER ADJUSTMENT
TS-430S AM WIDE/NARROW
FILTER SELECTION MORE
MORE
MORE
MORE MORE
TS-430S INTERNAL BEAT AT
28.415 & 21.526
TS-430S NOISE BLANKER
IMPROVEMENTS
TS-430S INTERMITTENT PLL
UNLOCK IN FM/AM
TS-430S DELETED,
SUPERCEDED BY #0895
TS-430S PLL UNLOCK AT
HIGH TEMPERATURE
TS-430S LOW/INTERMITTENT
RX / LPF RELAYS MORE
MORE
TS-440S OPERATION WITH
THE MC-85 MORE
TS-440S NOTCH FILTER
LOW FREQUENCY IMPROVEMENTS MORE
TS-440S PROTECTING Q33
FROM SHORT ON REMOTE PLUG MORE
TS-440S CASE SCREWS
BINDING IN THE HEAT SINK
TS-440S INTERMITTENT
OPERATION/ROM SOCKET MORE
TS-440S PLL UNLOCK IN
VCO'S DUE TO GLUE MORE
TS-440S PLL UNLOCK /
PLL #1
MORE
TS-440S S/M ALIGNMENT
PROCEDURE UPDATES
TS-450S DISTORTED TX
AUDIO WITH PACKET TERMINAL
TS-450S CALIBRATION
CABLE CHANGE
TS-450S DISTORTED TX
WITH PACKET TERMINAL MORE
TS-450S POOR TRANSMIT
AUDIO FREQUENCY RESPONSE
TS-450S LOW MIC GAIN
W/DSP-100
TS-450S PARTS CHANGES
FOR DRIVER TRANSISTORS
TS-450S CHANGE OF NOISY
ENCODER
TS-520 NOVICE
OPERATION - 75 WATTS
TS-520 AM
BROADCAST INTERFERENCE
TS-520 SERVICE
NOTES
TS-520 SM-220/BS-5
SWEEP INTERFERENCE
TS-520 IF OUT FOR
SM-220
TS-520 REPLACEMENT
FOR DS-1A IN TS820/TS520
TS-520S -6VDC SUPPLY FAILURE
TS-520S CW FREQUENCY SHIFT
TS-520S CW FILTER SELECT
CONTROL
TS-530S LOW VOLTAGE SUPPLY /
OPTIONAL IMPROVEMENTS
TS-530S IF UNIT Q2, Q7
PROTECTION
TS-660 MICROPROCESSOR
LATCH-UP
TS-690S CALIBRATION CABLE
CHANGE
TS-690S DISTORTED TX AUDIO
WITH PACKET TERMINAL
TS-690S DISTORTED TX WITH
PACKET TERMINAL MORE
TS-690S LOW MIC GAIN W/DSP-100
TS-700A REPEATER OPERATION
MODIFICATION (EUROPE)
TS-700A SERVICE NOTES
TS-700A 9 VOLT REGULATOR
REPLACEMENT
TS-820 AUX BAND
INSTALLATION (RX ONLY)
TS-820 RIT MODIFICATION
TS-820 MICROPHONE INPUT
ATTENUATOR
TS-820 REPLACEMENT FOR
DS-1A IN TS820/TS520
TS-820S SERVICE NOTES
TS-820S GENERAL ALIGNMENT
PROCEDURE
TS-820S SPEECH PROCESSOR
ALIGNMENT
TS-820S CW FILTER SELECT
CONTROL
TS-820S TA7201P SUBSTITUTION
PARTS KIT
TS-830S OPERATION ON 240V AC
TS-830S INTERMITTANT FREQUENCY
SHIFT
TS-830S LOW VOLTAGE SUPPLY
DRIFT/IMPROVEMENTS
TS-830S NOISE BLANKER
IMPROVEMENTS / CROSS MODULATION
TS-830S TRANSMITTER
"TALKBACK" FROM RF INTRUSION
TS-850S DISTORTED TX WITH
PACKET TERMINAL
TS-850S LOW OR NO RECEIVE
SENSISTIVITY/NO AUDIO
TS-850S NO AUDIO FROM VS-2
TS-850S S METER ADJUSTMENT
TS-850S CLICK NOISE WITH NOTCH
ON
TS-930S INCORRECT LINE VOLTAGE
SETTING
TS-930S CW HETERODYNE TONE
WITH VBT CONTROL
TS-930S SSB TX AUDIO TONE
QUALITY SN < 3080001
TS-930S LOSS OF RX SENSITIVITY
TS-930S PLL UNLOCK / BLANK
DISPLAY
TS-930S CW PITCH TONE SHIFT
WHEN MONI SWITCH IS ON
TS-930S CW VBT - SIMPLIFIED
ALIGNMENT
TS-930S RF FEEDBACK WHEN USING
EXTERNAL SPEAKER
TS-930S RX AUDIO OSCILLATION
TS-930S RF FEEDBACK INTO MIC
CIRCUIT
TS-930S ALC LEVEL DRIFT AT 28
MHZ
TS-930S POWER SUPPLY SURGE
PROTECTION
TS-930S 15 MTR INTERNAL BEAT
NOTE
TS-930S INTERMITTENT TX POWER
OUTPUT
TS-930S NOISY POWER SUPPLY FAN
TS-940S LCD CLOCK
DISPLAY ERRATIC OPERATION
TS-940S PLL UNLOCK
TS-940S ANTENNA TUNER
RELAY DAMAGE / MODIFICATION MORE
TS-940S PLL UNLOCK DUE
TO LOW LEVELS
TS-940S AVR UNIT
CAPACITOR CHANGE / FAILURE
TS-940S AGC CIRCUIT
IMPROVEMENTS MORE
TS-940S TRANSMITTER HUM
IN SSB MORE
TS-940S SIGNAL TO NOISE
RATIO IMPROVEMENT WITH NB
TS-940S VCO/CARRIER TO
NOISE RATIO IMPROVEMENTS MORE MORE
TS-940S SQUELCH
SWITCHING NOISE SN < 711XXXX MORE
TS-940S SSB TALK POWER
IMPROVEMENT S/N 601XXX-708XXX MORE
TS-940S ERRATIC DISPLAY
(REMOVE THE ROM SOCKET) MORE
TS-940S MRF-485 DRIVER
TRANSISTOR CHANGES (BLUE DOT) MORE
TS-950 HUM WITH
MONITOR ON S/N < 1060XXX
TS-950 NOISE WHEN
NB1 ON FOR SUB RECEIVER MORE
TS-950 14.200 MHZ
TRANSMIT SPUR S/N <1010XXX MORE
TS-950 LOW
PWR.OUTPUT AFTER TEMPERATURE PROTECT
TS-950 INFINITE
SWR AT BEGINNING OF TRANSMISSION
TS-950 SMOKE FROM
ANTENNA TUNER
TS-950S FINAL AMP.BIAS
CIRCUIT CHANGE MORE
TS-950S REAR COOLING FAN
/ POWER DOWN
TS-950SD SPEECH
PROCESSOR NOISE MORE MORE
TS-950SD LOW VS-2 AUDIO
TS-950SD N.B.GATE
SWITCHING NOISE
TS-950SD RX-TX
SWITCHING TIME WITH AMP MORE
TS-950SD RX DIGITAL
NOISE ON 10 & 15 METERS MORE
TS-950SD TWO SECOND TX
DELAY WITH MONI SWITCH ON MORE
TS-950SD RECEIVER NOISE
WITH VOLUME AT MINIMUM MORE
TS-950SD TX IMAGE ON
18.115 MHZ CAUSING DISTORTION MORE
TS-950SD 80 METER
SPURIOUS EMMISION ON 80 METERS MORE
TS-950SD TRANSMIT SPURS
MORE
TS-950SD SPUR ON 18.115
TS-950SDX RANDOM
TRANSMIT WHEN MODE IS CHANGED MORE
TS-950SDX NO BEEP IN
HEADPHONE WHEN USING MONO PHONES MORE
TS-950SDX DISTORTED
DRU-2 TRANSMIT AUDIO MORE
TS-950SDX K1EA VER.8
PROGRAM PROBLEMS - NEW EPROM MORE
TS-950SDX SPEECH
PROCESSOR ADJ / EXCESSIVE NOISE
TS-950SDX 3RD ORDER IMD
IMPROVMENTS
MORE
TS-950SDX KEY CLICK WITH
BUG TYPE KEY
TS-950SDX CLICK NOISE
WHEN NOTCH IS ON MORE
TS-950SDX INSTALLATION
OF YG-455S1
TS-950SDX NO VFO B AFTER
SPLIT OPERATION / MICRO CHANGE
TS-950SDX CARRIER POINT
ADJUSTMENT MORE
TS-950SDX SUB BAND
RESIDUAL NOISE MORE
TS-950SDX CHANGE OF
FINAL GATE RESISTOR TYPE
