Components Description; Electric Unit; Switch Unit; Cd Player Unit - Kenwood KDC-138/138CR Service Manual

● ELECTRIC UNIT (X34-564x-xx)
Ref. No. Application / Function
IC1 System µ-COM
IC2,3 E-VOL
IC4 Power Supply IC
IC6 Power IC
IC8 Reset IC
Q2 Servo+B AVR
Q3 Control SW for Servo+B
Q11 14V SW
Q12 14V SW
Q13 Control SW for IC4
Q14 Control SW for IC4
Q101 ACC DET
Q102 Serge DET
Q103 BU DET
Q104,105 Mute Control
Q301 Panel 5V SW
Q402 Quick Charge Voltage SW
Q701,702 Pre-out Mute SW
Q705 Mute Driver for Pre-out
Q801 Electric Discharge Circuit for C805 (SVR) ON when the base goes Lo.
Q901 DC Offset DET
Q902,903 DC Offset DET SW
● SWITCH UNIT (X16-616x-xx)
Ref. No. Application / Function
IC1 LCD Driver
IC2 Remote Control Sensor
● CD PLAYER UNIT (X32-5980-04)
Ref. No. Application / Function
CD Signal Processor
& MECHA µ-COM
IC1
RF Amplifi er responding
to CD-RW
IC2 3.3V REG
IC6 4ch BTL Driver

COMPONENTS DESCRIPTION

Controls FM/AM tuner, the changer, CD mechanism, panel, volume and tone.
Controls the source, volume and tone.
Outputs 5Vx2, 8.1Vx2, 10.2V, P-CON and P-ANT.
Amplifi es the front L/R and the rear L/R to 50W or 45W maximum.
Lo when detection voltage goes below 3.6V.
When Q3's base goes Hi, Servo+B AVR outputs 7.5V.
ON when the base goes Hi.
ON when the base goes Hi.
ON when the base goes Lo.
ON when the base goes Hi.
ON when the base goes Lo.
ON when the base goes Hi during ACC is applied.
When the base goes Hi, surge voltage is detected.
ON when the base goes Hi during BU is applied.
ON when the base goes Hi.
ON when the base goes Lo.
Charges voltage quickly when the base goes Hi.
When a base of the 4 transistors goes Hi, pre-out is muted.
ON when the base goes Lo.
ON when the base goes Hi after Q902's and Q903's outputs are separated.
ON when the bases go Lo after IC6's SP-OUTs (DC) are separated.
Focusing, tracking, sled and spindle servo processing.
Automatic adjustment (focusing, tracking, gain, offset and balance) operations.
Digital signal processing (DSP, PLL, sub-codes, CIRC error correction, audio data
interpolation processing) operations, and microcomputer function.
Generation of RF signal based on the signals from the APC circuit and the laser pick-up,
and generation of servo error (focusing error and tracking error) signals.
Detection of dropout, anti-shock, track crossing and off-tracking conditions, included gain
control function during CD-RW.
Supplies 3.3V to IC1 and the laser pick-up.
Focusing and tracking coil, sled and spindle motor driver, disc loading and eject operation.
KDC-138/138CR/139/139S
Operation / Condition / Compatibility
Operation / Condition / Compatibility
Operation / Condition / Compatibility
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