Technics ST-GT1000, Service Manual

Page: 26 / 64

1 3
2
CN102B
C B
24 23 22 21 20 19 18 17 16 15 14 13
1 2 3 4 5 6 7 8 9 10 11 12
FM
IF
IN
AM
MIX
OUT
REG
AM
IF
IN
GND SD ST
FM
DET
Vcc STRQ
FM/AM MONO
OSC
OUT
OSC
AFC
AM
RF
IN
AGC
AM
OUT
DET
OUT
PILOT
IN
MPX
IN
PILOT
OUT
Rch
Lch
Z102
1
2
3
4
6
1
2
3
10K
10K
B A D F C E
R127
470
C122 50V1
R122
2.7K
C121
50V0.47
C123 50V1
R131
68
C149
0.1
C147
1000P
R125
470
R126
1.5K
C148
0.01
R124
270
X102
A B
C106
0.01
C126
0.047
C127
16V22
C129
6.3V100
R1
19
10K
C1
17
0.018
C141
50V1 R141
1K
R145 100K
C143
4700P
B
A
C144
4700P R146 100K
R142
1K
C142
50V1
C1
18
0.018
C137
4700P
C131
100P
R123
68K
C138
0.01
C120
16V10
R121
22K
C139
4700P
R102
4.7K
C1
19
390P
C1
16
0.033
R143
22K
C1
15
25V4.7
R120
47K
C109
1000P
C1
14
50V3.3
R1
18
3.3K
A
D
B
C
R104
10K
C103
0.01
R109
330
C104
1000P
R105
470
CF201
R106
470K
1 3
2
CF202
IC101
LA1833MN TLM
FM/AM IF AMP,
DET/AM OSC,MIX/FM MPX
Q106
UN4111TA
POWER SUPPLY
(FM:ON)
CN101B
1 2 3 4 5 6 7
+B(2)
SD
STEYE
VT
+B(1)
T
.GND
A B
CL
DO
DI
Lch
OUT
CE
Rch
OUT
B
A
D A
1 2 3 4 5 6 7
DET
NC
To CONNECTOR CIRCUIT (CN204)
on SCHEMATIC DIAGRAM 7
C
To CONNECTOR CIRCUIT (CN203)
on SCHEMATIC DIAGRAM 7
C
R140
4.7K
Q110
2SC3311ARSTA
SWITCHING
R139
3.3K
Q102
2SC2787LTA
FM IF AMP
Q101
2SC2787LTA
FM IF AMP
R108
470K
C105
1000P
R107
330
SCHEMATIC DIAGRAM 2
FM
0.12V
P P
(0V)
0.7V
(0V)
3.8V
(0V)
14.7V
0V
(14.8V)
14.8V
(4.2V)
3.7V
2.5V 2.5V 1.4V 2.1V 2.1V 2.1V 1.9V 1.9V
(5.7V)
5.2V
(1.4V)
0V
(0.5V)
2.5V
2.1V 5.2V
(5.7V) 2.1V 2.1V 0V 0V 4.4V
(5V)
3.4V
(4.1V)
5.2V
(5.7V)
3.7V
(1.1V)
4.5V
(4.1V)
14.8V
7.3V
FM LINE +B
:POSITIVE VOLTAGE LINE :FM SIGNAL LINE :AM SIGNAL LINE :AM OSC SIGNAL LINE
7.3V 2V
2.6V
(2V)
(0.6V)
(0V)
0.7V
(0V)
3.8V
(2.1V) (2.1V) (0.9V)