Kenwood TK-285 Service Manual

Also see for TK-285: Service manual Instruction manual and user handbook

Contents

TK-285/(N)13IC1,2 IC Buffer amplifierIC3 IC Voltage detector / ResetIC4 IC Buffer amplifierIC5 IC Voltage regulator / 5MIC6 IC Voltage regulator / 5VIC7 IC Buffer amplifierIC8 IC D/A converter (Adjustment)IC9 IC Voltage regulator / 5CIC10 IC Active filter / For HSDoutIC11 IC Active filter / For LSDinIC12 IC FM IF systemIC13 IC Audio processorIC14 IC PLL systemIC16 IC DTMF decoderIC17 IC Flash memoryIC18 IC Active DBMIC19 IC MicroprocessorIC20 IC EEPROMIC21,22 IC Shift register / Output expanderIC23 IC Comparator (APC)IC24 IC Analog switchIC25 IC Active filterQ1 Transistor SwitchQ2 FET DC switch / 5RQ3 Transistor DC switch / 5TQ4 Transistor Noise amplifier / SquelchQ5 FET DC switch / SaveQ6 Transistor 2 nd IF W/N switch sets to on when NarrowDISPLAY UNIT (X54-3210-13)DESCRIPTION OF COMPONENTSQ7 Transistor 2 nd IF W/N switch sets to on when WideQ8 Transistor Ripple filterQ9 Transistor DC switch / W/N audio amplitude adjustQ10 Transistor AF mute switchQ11 FET Mute switchQ12 Transistor IF amplifierQ13 FET Mute switch / MIC line muteQ14 FET DC switchQ15 FET DET muteQ16 Transistor PLL IC fin amplifierQ17 FET Mute switch / MIC line muteQ18 Transistor Buffer amplifierQ19 Transistor Clock frequency shiftQ20 Transistor RF amplifier / TX driverQ21 FET DC switchQ22 Transistor DC switchQ23 FET DC switchQ24 FET RF amplifierQ25 Transistor DC switchD1 Diode Reverse protectionD2 Diode Overload protectionD3 Diode Reverse current protectionD4 Diode Noise detectionD5 Diode RF switch (2nd IF wide/narrow)D6 Diode Current steeringD7 Diode RF switch (2nd IF wide/narrow)D8 Diode Voltage clampD9 Diode TX/RX switchD10 Diode Overload protectionD11 Diode Speed upD12,14 Diode ANT switchD16,17 Diode Varactor tuningD18,19 Diode Surge absorptionD20,21 Diode Varactor tuningD22 Diode ANT switchD23 Diode TX/RX switchD24 Diode Voltage dropD401 Diode ANT switchD402 Diode DischargeIC300 IC Audio power amplifierIC301 IC Counter /Key scanQ300 FET DC switch / INT MIC on/offQ301 FET DC switchQ302 Transistor DC switch / LED (Red) driverQ303 Transistor DC switch / LED (Green) driverQ304 Transistor DC switchQ305 Transistor Current driver / Audio amp AVRQ306 Transistor DC switchQ307 Transistor Current driver / LCD back light LED AVRQ308 FET DC switch / SP INT/EXTQ309 Transistor Temperature compensationQ310 FET Mute switchD300 Zener diode Surge absorptionD301 LED LED / Red, GreenD302 Diode Quick discharge /AF muteD303 Zener diode Voltage referenceD304 Diode Voltage referenceD305~310 LED LCD back lightD315~318 Diode Reverse current preventionD319~321 Zener diode Surge absorptionRef. No. Use/Function Operation/ConditionRef. No. Use/Function Operation/ConditionTX-RX UNIT (X57-619X-XX)Ref. No. Use/Function Operation/ConditionQ1 FET DC switchQ2,3 FET VCO oscillationQ4 Transistor DC switchQ5 Transistor RF Buffer amplifierD1-D8 Diode Frequency controlD9 Diode TX modulationRef. No. Use/Function Operation/ConditionSUB UNIT (X58-473X-XX)