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MHC-GRX9900
– 23 – – 24 –
7-3. BLOCK DIAGRAM – MAIN Section –
DBFB CONTROL
SWITCH
Q111
BASS FREQUENCY
CONTROL SWITCH
Q201
RESET SIGNAL
GENERATOR
IC502
POWER AMP
IC801
CD-L
J101 (1/2)
A
(Page 20)
(Page 22)
C
(Page 22)
PB-L
B
(Page 25)
SPEANA
D
R-CH
R-CH
R-CH
05
FM/AM TUNER UNIT
VOLUME
CONTROL
CPU
INTERFACE
BASS BOOST
CONTROL
CIRCUIT
INPUT
SELECT
SWITCH
SOUND
CONTROL
CIRCUIT
GRAPHIC EQUALIZER
CONTROL CIRCUIT
R-CH
FEED BACK
SWITCH
Q112
R-CH
COMMAND
F OUT2
BUF
OUT2
VOL
IN2
+
+
R-CH
R-CH
R-CH
R-CH
D141
R-CH
+
+
+
MIC LEVEL
RV712
MIC AMP
IC712 (2/2)
MUTING
Q113
OVER LOAD
DETECT
Q801
TEMPERATURE
DETECT SWITCH
Q831, 832
DC DETECT
SWITCH
Q433, 434
RESET SWITCH
Q501
RELAY
DRIVE
Q431
INPUT SELECT SWITCH,
GRAPHIC EQUALIZER CONTROL,
ELECTRICAL VOLUME
IC101
IN E2
IN D2
IN B2
IN A2
IN C2
KEY IN2
KEY IN1
KEY OUT 2
KEY OUT 1
L+R
DATA
CLOCK
LATCH
493-DATA
493-CLK
493-LATCH
DBFB-H/L
BASS FREQ.
PROTECTOR
XC-OUT
X613
16MHz
X601
32.768kHz
XC-IN
X-OUT
X-IN
BB B2,
BB A2
MIC IN
SUPER
WOOFER
REC A2
REC-L
D191
REC B2
• SIGNAL PATH
: CD PLAY
: TAPE PLAY
: RECORD
: TUNER (FM/AM)
: MIC INPUT
TH831
+5V
R-CH
+
R-CH
R-CH
M501
(FAN)
R-CH
–1
–2
+
MUTING
Q191
MUTING
Q411, 471
FAN MOTOR
DRIVE
Q401, 402
PROTECT
SWITCH
Q192
R-CH
R-CH
OVER LOAD
DETECT SWITCH
Q432
PROTECT SWITCH
Q439
PROTECT SWITCH
Q435, 436
OVER LOAD
DETECT SWITCH
Q437
STANDBY SWITCH
Q803, 804, 881
MUTING CONTROL
SWITCH
Q508, 509
MUTING CONTROL
SWITCH
Q412
J701
PHONES
TM401
SPEAKER
IMPEDANCE
USE 6 – 16
Ω
J711
MIX MIC
L
L
R
R
VIDEO
(AUDIO) IN
MD IN
J101 (2/2)
L
R
MD OUT
J191
SUPER
WOOFER
ANTENNA
ST-L
FM ANT
(GRX9900)
FM ANT
AM ANT
AM ANT
ST-R
ST-MUTE
STEREO
TUNED
ST-DIN
ST-DOUT
ST-CLK
ST-CE
ST-MUTE
STEREO
TUNED
ST-DOUT
ST-DIN
ST-CLK
ST-CE
FM
75
Ω
AM
38, 39
D607
D644
D803
RY401
+
–
–
+
SYSTEM CONTROLLER
IC501 (3/4)
+
MIC AMP
IC712 (1/2)
(Page 25)
RESET
E
27
F-RELAY
3
11
10
13
15
7
44
STK-MUTE
1
LINE-MUTE
RESET
6
12
AC-CUT 22
RY-SW 36
47
48
38
60 5
59 6
30
2
58
57
42
41
72
36
34
BUF IN2
37
32
33
49
50
51
54
21
R
20
53
52
55
65
66
68
69
67
M
L
R