Kenwood TS-820 Operating Manual

Also see for TS-820: Service manual Service manual Service manual Operating manual Manual

Contents

VOX-VR B O A R D 1x54-1190-001Three variable resistors. VOX GAIN. ANTI VOX and DELAY.are directly mounted on a printed circult board.5V AVR B O A R D (OPTION1 1x43-1220-001Thts is a 5V power s t a b ~ l ~ z e rused for the counter unlt Ituses IC to provlde rated voltage wlthout maklng any adjust-mentsM A R K E R 8 0 A R D 1x52-0005-011The MARKER board holds the 1 0 0 kHz crystal oscillator101) and a 2 5 kHz multivibrator 102 and 0 3 ) to producemarker signals at 2 5 kHz intervals to calibrate the TS-820.0 4 amplif~esthe calibrator signal^RECTIFIER B O A R D 1x43-1090-021This board holds all of the diode rectillers for the power sup^ply section of the transceiver. D l through D 4 rectlly thehlgh voltage. D 5 rectifies the 3 0 0 volt supply. D6 rectifiesthe 2 1 0 volt supply. D 7 rectifies the 9 0 volt supply. and D 8through D l 1 rectify the 13.8 VDC supply.H V ( H I G H VOLTAGE) 8 0 A R D1x43-1110-001Thls voltage divider crrcuit s~lppllesa high voltage meterings~gnalfor the HV meter reading and also a low voltagescreen source used in the TUN mode of 'operation.INDICATOR B O A R D 1x54-1180-00)Thls clrcult controls the light emitting diodes which indicate1when the RIT circuit is on, when the fixed frequency oscilla-- tor IS operating. or when the VFO is oscjllat~ngRELAY B O A R D 1x43-1190-001F I N A L B O A R D 1x56-12'00-00)T h ~ sunit ~ncludesall the circuits of the power amplifier ofthe flnal stage wrth the exception of the p i ~ n e t w o r kclrcuit atthe output side.Fig. 2 2 F I N A L Board5.3 F I N A L STAGE P O W E R AMPLIFIERThjs a m p l ~ f ~ e rdeltvers 2 0 0 W PEP tnput by 2 transmli powertubes (S2001A) I t is equlpped w ~ t ha cool~ngfan to avoidtemperature rlse during operattonT h ~ sunit holds the stand-by relay. a 5V power stabilizer tofeed power to the PLL circuit. and smoothing capacitors toobtain low voltage DC power.The relay of thls unit 1s used to select OC signal for con-trolling block b ~ a s ,cross channel operation. etc