Components Description - Kenwood KDC-138 Service Manual

● ELECTRIC UNIT (X34-56xx-xx)
Ref. No. Application / Function
IC1 System μ-COM
IC2 E-VOL
IC4 Power Supply IC
IC6 Power IC
IC7 RDS IC
IC8 Reset IC
Q2 Servo+B AVR
Q3 Control SW for Servo+B
Q7 VFD+B SW
Q8 VFD+B AVR
Q9 Control SW for VFD+B
Q10 VFD+B SW
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
Q701~704 Pre-out Mute SW
Q705 Mute Driver for Pre-out
Q801 Electric Discharge Circuit for C805 (SVR) ON when the base goes Lo.

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 maximum.
RDS decoder.
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.
When Q9's base goes Hi, Servo+B AVR outputs 10.5V.
ON when the base goes Hi.
ON when Q7's 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.
When a base of the 4 transistors goes Hi, pre-out is muted.
ON when the base goes Lo.
X34-56xx-xx
Operation / Condition / Compatibility
3