DS-90/90A
Feb. 2000
12
INPUT LEVEL
LF TRIM
Analog/Digital
HF OUT
LF OUT
HOT
COLD
Frame Ground
HF TRIM
TO DA BOARD
CN3
HEAD AMP BOARD
-15V
10kHz -4.0dBm 489mV
1kHz 0dBm 775mV
1kHz 0dBm 775mV
10kHz -4.0dBm 489mV
1kHz +0.7dBm
840mV
10kHz -4.0dBm 489mV
TO POWER AMP BOARD CN4
+15
+15
- 15
- 15
- 15
A
A
A
A
A
A
A
A
A
A
- 15
+15
- 15
A
- 15
- 15
A
A
A
- 15
A
A
A
A
A
A
A
A
- 15
A
SW1B
SSSF120500
21
23
22
Q28
2SC2240GR
3
1
2
Q32
2SC2240GR
3
1
2
Q31
2SC2240GR
3
1
2
Q29
2SC2240GR
3
1
2
Q30
2SC2240GR
3
1
2
R106
10k
R105
10k
R108
10k
R103
470k
R95
47
R83
10k
R85
56k
R93
10k
R82
10k
R90
12k
R92
10k
R88
12k
R80
10k
R84
10k
R98
10k
R111
10k
R102
10k
R94
10k
R91
10k
C42
0.15
C38
0.15
C37
0.0039
C34
0.0039
C36
0.0039
C33
0.0039
C52
0.0047
C56
0.0039
C35
0.0039
R86
12k
R89
12k
C51
0.0047
C44
0.0047
IC6A
TL072CP
+
-
2
3
1
IC6B
TL072CP
+
-
6
5
7
IC6C
TL072CP
+
-
8
4
R113
180k
R110
100k
R109
180k
R115
47k
R101
10k
R114
10k
C55
0.18
C54
0.18
C46
0.22
R116
22k
IC7C
TL072CP
+
-
8
4
IC7B
TL072CP
+
-
6
5
7
R96
47
C47
0.22
VR1A
RK11K1120A0A
10kA
1
2
3
4
VR2A
RK11K112002F
50kB CC
1
2
3
4
C57
10/35
C49
10/35
C41
10/35
C43
10/35
C45
0.0047
SW1A
SSSF120500
11
13
12
R107 180k
R104
10k
IC7A
TL072CP
+
-
2
3
1
R100
180k
R112
10k
C58
0.047
R87
10k
CN5
S5B-PH-K-S
1
1 2
2 3
3 4
4 5
5
C53
0.47
CN6
S4B-PH-K-S
1
1
2
2
3
3
4
4
R81
470k
C48
0.047
JK2
NCJ9FI-H
TS
T
RS
R
SS
S
FG
2
3
1
4
5
6
7
8
9
10
VR3A
RK11K112002K
10kB CC
1
2
3
4
C40
10/35
R97
470k
C32
10/35
R99
10k
C31
10/35
C59
0.1
C39
10/35
+15
+15
+15
+15
+15
+15
CIRCUIT DIAGRAM (ANALOG SHEET) 1/4
