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MHC-GRX9900
7-4. BLOCK DIAGRAM – DISPLAY/KEY CONTROL/POWER SUPPLY Section –
– 25 – – 26 –
REGULATOR
CONTROL SWITCH
Q903, 923
D925
D501, 502
+7V
REGULATOR
IC901
–26V
(FL DRIVER (IC601) B–)
+12V
REGULATOR
IC903
+10V
REGULATOR
Q909
–7V
REGULATOR
Q914, 951, 952
+7V
REGULATOR
Q901, 902, 913
ST +10V
(FM/AM TUNER UNIT B+)
TC M+12V
(TC MOTOR SECTION B+)
CD M+7V
(CD MOTOR SECTION B+)
B+ SWITCH
Q907, 908
D509
B+ SWITCH
Q904, 905
+5V
REGULATOR
IC902
RECT
D907 – 910
RECT
D901 – 904
POWER AMP (IC801),
PROTECTOR CIRCUIT
POWER TRANSFORMER
T951
RECT
D832
RECT
D831
VOLTAGE
SELECTOR
S951
RECT
D971
–26V REGULATOR
Q971
AC IN
+7V
TC, PANEL,
AUDIO
–7V
FAN MOTOR B–
VF1
TO FLUORESCENT
INDICATOR TUBE
(FL601)
VF2
B+
B–
B+
B–
REMOTE CONTROL
RECEIVER
IC602
GRID DRIVE
Q611 – 616
FLUORESCENT INDICATOR TUBE DRIVER,
KEY CONTROL
IC601
SYSTEM CONTROLLER
IC501 (4/4)
LED DRIVER
IC604
BAND-PASS FILTER
IC603
Q603
LED +5V
S LOW FREQ (BPF0)
18
BPF2
19
BPF3
20
BPF4
GRID DRIVE
Q610
DET
DET
B.P.F.
21
ALL BAND (L+R)
REC IN
LINE
IN
1 SIRCS
ROTARY
ENCODER
S601
ROTARY
ENCODER
S602
2 JOG-A
9 VOL-A
8 JOG-B
10
72
70
VOL-B
XOUT
XIN
B+ SWITCH
Q601, 602
LED DRIVE
Q605
KEY0 – KEY3
BPF1
F01
F04
F05
F06
F02
G1
(Page 23)
(Page 23)
D
D611 – 615, 619,
D620, 622 – 626,
D631 – 634, 801 – 803
SPEANA
L SEL
7
TIMER LED 26
LED DATA
5
LED SCK
3
LED LAT
DATA
CLK
4
13
14
15
45
I2C DATA
I2C CLK
IIC-DATA
IIC-CLK
RESET
RESET
17
79
78
29
GRADATION R/WAKE UP
WAKE UP
22
GRADATION L
15
30
42
43
CD-POWER
5
POWER
2
73
16
14
13
12
L+R
11
16
17
4
6
11 – 14
S1 – S22
46 – 67
G13 – G18
32 – 27
G2 – G12
44 – 42, 40 – 33
17, 19 – 23, 2, 3, 5, 7, 10, 11
P1 – P6, P8, P9, P11, P12, P15, P16
S601
(JOG DIAL)
S611 – 630,
S637 – 650, 801 – 807
05
S602
VOLUME
X601
12.5MHz
E
STB
LED DRIVE
Q604, 620
STBY LED 39
D636
TIMER SELECT
LED DRIVE
Q607
D608
(LEFT)
D609
(RIGHT)
D608, 609
(FOR ILLUMINATION DISPLAY)
D804
I/
u
(GRX9900)
(GRX9900)
(GRX9900)
(RXD9)
(RXD9)
CD D+5V, CD A+5V
CD MECHANISM DECK
SECTION B+
+5V
SYSTEM CONTROLLER
(IC501) B+
D+5V
M62493FP (IC101),
CD SENSOR CIRCUIT B+
D923
D405 – 407
(GRX9900)
(RXD9)
D+5V
(TAPE DECK SECTION B+)
+5V (STBY)
(PANEL SECTION B+)
LED +5V
(PANEL SECTION B+)
D922
(GRX9900)
(RXD9)
D924
(GRX9900)
(RXD9)
FLUORESCENT INDICATOR TUBE
FL601
18
LED DRIVE
Q608