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XR-4950X/4954X
18
18
7-1.
BLOCK DIAGRAMS – TUNER/TAPE/MAIN SECTION –
SECTION 7
DIAGRAMS
09
TAPEEQUALIZER METAL, AMS, DOLBY
IC301
37
39
R-CH
PBF
IN2
FWD
L-CH
HP901
(PLAYBACK)
FWD
R-CH
REV
L-CH
REV
R-CH
PBR
IN2
R-CH
R-CH
R-CH
R-CH
R-CH
R-CH
EQ AMP
2
4
MUTE
DOLBY
NR AMP
PB
OUT2
TAPE
IN2
AMS
DET
+
NROUT
19
DRSW
18
TAPESW
17
16
20
INSW
TAPE ATT
DOLBY
AMSON
AMSIN
MSSW
7
LINE
OUT2
14
MS
OUT
SE1L
MPX
AM DET
SE2L
SDA
SCL
EXT-AT
13
1
11
12
4
VOLUME
CONTROL
CIRCUIT
LOUDNESS
CONTROL
CIRCUIT
DIGITAL CONTROL
CIRCUIT
IIC BUS
LOUDNESS
CONTROL
CIRCUIT
INPUT
SELECTOR
AM IF
INPUT SELECT,
ELECTRICAL VOLUME
STEREO DECODER
IC331
SOFT
MUTE
TONE
CONTROL
CIRCUIT
FADER
FADER
29
18
20 21
OUT LR
30
OUT LF
DATA
CLOCK
MASTER MICRO COMPUTER
IC501 (2/3)
46
VOL ATT
47
I2C CKO
45
I2C SIO
BEEP
J331
AUDIO OUT
(REAR)
L
R
15
TEST
49
AMP ATT
40
TELATT
50
ATT
MUTE DRIVE
Q621
MUTING
CONTROL SWITCH
Q622
AMP ON
BATT B+
D622
D588
D621
FRONT L (+)
1
AUX
12
14
5
3
FL+
FL–
21
23
FR+
FR–
FL-IN
FR-IN
11
9
7
RL+
RL–
RL-IN
15
22
17
19
RR+
RR–
RR-IN
4
TEL MUTE
Q583
CN781 (1/2)
(POWER CONNECTOR)
POWER AMP
IC751
FRONT L (–)
9
FRONT R (+)
4
FRONT R (–)
12
REAR L (+)
2
REAR L (–)
10
REAR R (+)
3
REAR R (–)
11
13
MUTING
Q171
MUTING
Q271
MUTING
Q181
STNBY
MUTE
MUTING
Q281
R-CH
R-CH
CAPSTAN/REEL
MOTOR DRIVE
Q354
CMON
BATT B+
M
M901
CAPSTAN/REEL
MOTOR
TAPE REG DRIVE
Q352
LMEJ
TAPON
LMLOD
BATT B+
IN2
IN1
LOADING MOTOR DRIVE
IC351
9
DRIVE
4
3
TAPE REGULATOR
Q351
OPERATION
MOTOR
TESTIN
39
TAPE OPERATION
SWITCH
BUFFER
TAKE-UP
REEL
SENSOR
SUPPLY
REEL
SENSOR
REEL SENSOR BOARD
REEL
85 – 88
POS0 – POS3
TAPE
DETECT
EJECT/FF/REW/
REV/FWD MODE DETECT
TEL
• SIGNAL PATH
: MW(SW)
: FM
: TAPE PLAYBACK
53
91
90
89
92
52
57
55
48
84
MOTOR DRIVE
SWITCH
Q353
16
35
1
4
2
FM-ANT
AM-ANT
14
S-METER
17
SDA-FEP
SCL
7
3
77
SW SHIFT
18
SCL-FEP
TU ATT
SW SHIFT
VSM
2
E2P SIO
74
75
E2P CKO
10
8
13
MPX
AM DET
12
MASTER MICRO COMPUTER
IC501 (1/3)
FM/AM TUNER
TU1
MUTING
Q11
MUTING CONTROL
SWITCH
Q31
MUTING
Q21
FM AGC
SDA
FM AGC
J1
(FM/AM ANTENNA)
11
BU+B
TU5V
TU8V
EEP VDD
10
VDD
5
VCC
19
AM IF
51
D31
w w w . x i a o y u 1 6 3 . c o m
Q Q 3 7 6 3 1 5 1 5 0
9
9
2
8
9
4
2
9
8
T E L
1 3 9 4 2 2 9 6 5 1 3
9
9
2
8
9
4
2
9
8
0
5
1
5
1
3
6
7
3
Q
Q
TEL 13942296513 QQ 376315150 892498299
TEL 13942296513 QQ 376315150 892498299