Sony XR-4950X Service Manual page 21

• IC Block Diagrams
– MAIN Board –
IC331 TDA7402TR
33 32 31 30
MONO-
FADER
ACINLF 34
FRONT
35
SWINR ACIN
OUTPUT
SWINL 36
REAR
SELECTOR
ACOUTR 37
SW
MAIN
ACOUTL 38 SECOND
CREF 39
LP
VOICE
BANDPASS
HP
BASS
TREBLE
VOLUME
SOFTMUTE
COMPANDER
LOUDNESS LOUDNESS
MUX 40
IN-GAIN
+
IN-GAIN
MUTE
+AUTO ZERO
MAIN SOURCE MIXING SECOND SOURCE
SELECTOR SELECTOR SELECTOR
MD1 41
MAIN
MD1G 42
INPUT
MULTIPLEXER
FM
MD2 43
PHONO
MD2G 44
MAIN CH0 AUX AM
1 2 3 4 5 6 7 8 9 10 11
29 28 27 26 25 24 23
MIXER
MONO- MONO- MONO- MONO- MONO-
FADER FADER FADER FADER FADER
SUBWOOFER
+PHASE
CONTROL
22 VDD
21 SCL
20 SDA
SUPPLY 19 GND
HIGH-CUT
18 SM
S&H PULSE
FORMER
25kHz QUAL 17 QUAL
LP
16 MPOUT
MULTIPATH
DEMODULATOR
DETECTOR
15 MPIN
+STEREO ADJUST
+STEREO BLAND
BEEP
D/A
14 LEVEL
CONVERTER
PILOT
CANCELATION
PIL DET
PLL
80kHz
13 MPX
LP
AM/FM
12 AMIF
NOISE BLANKER
IC301 CXA2509AQ-T4
30 29 28 27 26 25
120µ/70µ
T2
+ –
– +
NR BIAS
PBFB2 31
X1
32
PBRIN2
TAPE/AUX
33 F2
PBREF2
TAPE EQ
PBFIN2 34
FWD/RVS
VCT 35
VCT
PBGND VCC
36
+ LPF
+
–
PBFIN1 37
F3
F1
PBREF1 38
X1
PBRIN1 39
PBFB1 40
T1
120µ/70µ
24dB
1 2 3 4 5 6 7 8 9
IC611 BA4908-V3
REGULATOR
OVER VOLTAGE
PROTECT
–
+
1 2 3 4 5 6 7 8 9
21 21
IC351 LB1930M-TLM
VCC
1
BUFFER
NC 2
IN1 3
24 23 22 21
CONTROL
CIRCUIT
24dB
IN2 4
BUFFER
S-GND 5
20 MSMODE
MS
19 DRSW
MODE
18
TAPESW
17 INSW
16 NC
15 NC
MS ON/
OFF
DETECT
14
MSOUT
13 DGND
12 MSTC
11 G1FB
10
10 11 12
XR-4950X
10 NC
9 OUT1
MOTOR
DRIVE
8 NC
CIRCUIT
7 OUT2
6 P-GND