Preamp Pcb Schematic (Post Amp) - Cambridge Audio 840A Service Manual

C35
47N PE 63V
C16
-15V
3
VOL OUT LEFT 10U NP 16V 2
R77
47K
390R
R75
R76
390R
P2
PAD
GROUND REINFORCE
P3
PAD
C33
POST AMPLIFIER
18 pF
C34
15 pF
C17
5
VOL OUT RIGHT 10U NP 16V 6
R80
47K
R78
390R
R79
390R
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Cambridge Audio Azur 840A Amplifier
+15V C31
R106
PREAMP OUT L
470R
47U NP 25V
R107
C23
47K
100nF ceramic
U12:A
R81
1
220R
NE5532
100nF ceramic
C26
-15V
HI = NORMAL
OVERTEMP
HI = NORMAL DC OFFSET
HI = NORMAL OVERLOAD
HI = NORMAL CLIP DETECT
D3
5V1 1N4148
LO = ON XD ON/OFF
U12:B
R82
7
220R
NE5532
C32
R108
470R
47U NP 25V
R109
47K
AP16365/4 Preamp PCB Schematic (Post Amp)
PREAMP PCB - POWER AMP LEFT PCB CONNS
+9V
+5V
LOGIC GND
SPEAKER TEST
R84
47K
MAINS FAIL
OUTPUT RELAY A
OUTPUT RELAY B
D1 D2 PHONES R
PHONES L
1N4148
PHONES GND
LOGIC GND
PREAMP PCB - POWER AMP RIGHT PCB CONN
PREAMP OUT R
CN10
1 AUDIO TO L POWER AMP
2
JST 2.5MM B2B-XH-A
CN4
1
+15V
2
3
4
SPEAKER TEST
5
CLIP
6
OVERLOAD
C7
7
DC OFFSET
8 10u 25V
OVERTEMP
9
XD ON/OFF
10
11
C30
12
+9V
13 10u 25V
14 +5V
15
16
FFC 16WAY
-15V
OPAMP DECOUPLING LOGIC GND
MAINS FAIL IN MAINS FAIL IN
MAINS ON/OFF RELAY
INRUSH RELAY
CN12
PREAMP PCB - PSU PCB CONN
1
AUDIO TO R POWER AMP
2
JST 2.5MM B2B-XH-A
CN5
1
2
3
4
5
6
7
8
9
10
11
12
FFC 12WAY
21