Preamp Pcb Schematic (Tone Control) - Cambridge Audio 840A Service Manual

C38
1N PE 63V
TREBLE ALPHA RD902PF
6 4
VR1:B
R3 R2
C1
1K1 1K1
1N5 PE 63V
R5 R1 R4
2K2 4K7 2K2
6 4
VR2:B
BASS
ALPHA RD902PF
C2
680n poly
CN3
P1
1
GROUND REINFORCE
2
PAD
3
4
TONE CONTROL
5
PREAMP OUT L
6
PREAMP OUT R
JST 2,5MM B6B-XH-A
C39
1N PE 63V
TREBLE ALPHA RD902PF
3 1
VR1:A
R7
R8
1K1
C4
1K1
1N5 PE 63V
R10 R6 R9
2K2 4K7 2K2
+15V
ALPHA RD902PF
3 1
BASS VR2:A
C5
680n poly
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Cambridge Audio Azur 840A Amplifier
C9
470U 10V EL
+15V
C8
47N PE 63V
C36
100pF
2K2
R16
C3
C10
3
10pF
1
R15
2
470U 10V EL
2K2
NE5532
U1:A
U1:B
5
7
6
NE5532
-15V
C11
470U 10V EL
C37
100pF
R18
2K2
C6
U2:B C12
5
10p 7
R17
C13
6
NE5532 470U 10V EL
2K2
47N PE 63V
U2:A
3
1
2
NE5532
C14
47N PE 63V
-15V
AP16365/4 Preamp PCB Schematic (Tone Control)
SW1:A
SW-DPDT
R11 R97
DEFEAT
47k 150R
RL17:B RL18:B
4 4
3
5 5
RELAY RELAY
R22
150R
R85
390R
R105 R87
2K2 2K2
R13
47k
2.5 dB 3.75 dB
BALANCE CONTROL
SW1:B
SW-DPDT
R12
R98
DEFEAT
47k
150R
RL17:C RL18:C
7 7
6
8 8
RELAY RELAY
R90
R96
150R
390R
R14
47k
R91 R93
2K2 2K2
RL15:C
7
6
8
RELAY
RL15:B
C18
U9:B
4
3 NE5532
5 10U NP 16V
5
RELAY
RL19:B
6
4
3 3
5
RELAY
R99
R88
47K
1K
LEFT
R86
390R
R89
2K2
5.5 dB
BALANCE BUFFER
RL16:C
7
6
8
RELAY
RL16:B
C24
4
3
U9:A
5
10U NP 16V 3
RELAY
RL19:C
2
7
NE5532
6 6
8
RELAY
R101
47K
R94
RIGHT
1K
-15V
R92
390R
R95
2K2
C21
TO VOLUME LEFT
7
1000U 10V EL
R103
47K
+15V
C15
47N PE 63V
C25
TO VOLUME RIGHT
1
1000U 10V EL
R102
47K
C22
47N PE 63V
20