Block Diagram; Components Description - Kenwood KAC-7202 Service Manual

KAC-7202/7252
PREAMPLIFIER UNIT (X08-4190-1x)
Ref. No.
IC1 HPF
IC2 Phase reversal amplifier (Lch only)
IC3 LPF
IC4~6 Bass-boost circuit
IC7 Bass-boost mixing amplifier
AUDIO UNIT (X09-5830-1x)
Ref. No.
IC1,12,16 Input isolation amplifier
IC5 DC/DC converter
IC6 Temperature detection comparator
IC7,8 For adjusting bass-boost f
IC9 For adjusting bass-boost gain
IC13 Bass-boost phase shifter
IC15 Bass-boost mixing amplifier
±15V AVR
Q1,2
Q3~8 DC/DC converter FET
Q9~12 DC/DC converter FET driver
Q13,14 For controlling DC/DC converter FET driver
No. ITEM
IDLE
1
CURRENT
2

BLOCK DIAGRAM

ISO AMP
IC12,16
IC1(X08)
L
HPF
LINE IN
50-200Hz
L
IC3(X08)
MO/ST
LINE OUT
LPF
R SENS
50-200Hz
LINE OUT
R
HPF
LINE IN
50-200Hz
IC1
L
SP IN
R
SP IN

COMPONENTS DESCRIPTION

Application / Function
Application / Function
ADJUSTMENT
ALIGNMENT POINT
VR1 (Lch)
VR2 (Rch)
LPF/OFF/HPF
POWER AMP
IC7-9,13,15
Q201-258
Q241,242
BASS
MUTE
BOOST
40-100Hz
BASS
BOOST MUTE
40-100Hz
REMOTE
CONTROL
CONTROL
f, GAIN
f=40-100Hz
GAIN=0-18dB
15V AVR D.D. CON.
Ref. No.
Q101
Q201~204
Q209,210
Q205~208
Q211,213
Q220,222~227,229
Q241,242
Q251~258
Q280,282
Q601,615~618
Q602
Q603
Q604,605
Q606
Q607,608,619,620
Q609
Q610
Q611,612
Q613,614
Q621,622
Q623
METHOD
Connect a DC voltmeter
between check land
(Refer to PC BOARD)
SP OUT L
SP OUT R
P-CON
BATT
GND
Application / Function
Remote controller reference voltage
Power amplifier initial step differential driving
Current limiter
Power amplifier second step differential driving
Temperature detection for idling
Power amplifier final
Power amplifier mute
Power amplifier driver
Power amplifier ATT (-3dB)
Power-ON shock preventer circuit
P-Con OFF detection
Mute drive
P-Con control circuit
Excess voltage detection
Temperature detection control circuit
Fan power supply
Excess current detection
DC detection
DC detection for latch
For LED control
Temperature detection control circuit
ALIGN FOR NOTE
After Power on
2.5mV
5 minutes