Cambridge Audio 740A User Manual

Cambridge Audio Azur 740A Amplifier
AP19794/4 Amplifier Circuit Diagram (Protection)
LE1
LE2
R34
1/8W Metal Film 2K2
R26
1/8W Metal Film 2K2
R84
2K2 1/8W Metal Film
R102
1/8W Metal Film
47K
R74 47K
1/8W Metal Film
D16
Zener 5V1 1/2W
DGND
PIC VI/Short
R79
1/8W Metal Film 18K
D18 1N4148 Signal Diode
R101
1/8W Metal Film
47K
R33
51K 1/4W Metal Film R25
51K 1/4W Metal Film
R82 2K2 1/8W Metal Film
+50V. L
-50V. L
R83 2K2
1/8W Metal Film
R81 2K2 1/8W Metal Film
RE1 RE2
R72
1/8W Metal Film 2K2
R64 1/8W Metal Film 2K2
R94
2K2 1/8W Metal Film
R71
51K 1/4W Metal Film R62
51K 1/4W Metal Film
R92 2K2
1/8W Metal Film
+50V. R
-50V. R
R93
2K2
1/8W Metal Film
R91 2K2
1/8W Metal Film
ROLO
Q37
MPSA42
NPN Signal
Q36
MPSA42 NPN Signal
Q40
MPSA42 NPN Signal
Q41 MPSA42 NPN Signal
Q33 MPSA92
PNP Signal
D6
1N4148 Signal Diode
D9 1N4148 Signal Diode
D7
1N4148
Signal Diode
D10 1N4148
Signal Diode
DGND
DGND
R63
100K 1/8W Metal Film
R42 100K 1/8W Metal Film R109 100K 1/8W Metal Film
RAMP
+50V P -50V P
RO
PIC DC Detect
D5
1N4148 Signal Diode
D8
1N4148 Signal Diode
R112
100K 1/8W Metal Film
LAMP
LO
RO
D25
1N4148
Signal Diode
R96 1/8W Metal Film
100K
R95
1/8W Metal Film 15K
R97
1/8W Metal Film 120K
R99 1/8W Metal Film
100K
R77
10k 1/8W Metal Film
LO
D24
1N4148 Signal Diode
R86 1/8W Metal Film 100K R85 1/8W Metal Film 15K
R100
1/8W Metal Film 15K
+50V. R
R98
1/8W Metal Film
120K
D17 Zener 5V1 1/2W
DGND
PIC Clip Detect
1
2
3
4 5
CN6 5Way Straight Header
To input PCB/To PIC
DGND
PIC DC Detect
PIC Clip Detect PIC VI/ShortTemp Sense
DGND
R75 1/8W Metal Film 4K7
TH1
PTC Thermistor 100 Degree 500R Mounted on Heatsink
C64 Ceramic 220pF 50V
C63 220pF 50V Ceramic
C69
220pF 50V
Ceramic
C70
Ceramic
220pF 50V
C68 10uF 63V
Electrolytic
C62
Ceramic
4.7nF 50V
R88
1/8W Metal Film
100K
R87
1/8W Metal Film 120K
R89
1/8W Metal Film 15K
R90 1/8W Metal Film 120K
C55 NP Electrolytic 10uF 25V
C54
NP Electrolytic 10uF 25V
1 2 3 4
5
6 7 8
CN2
Right Angle Pin Header 8Way
1
2
3
4
5
6
7
8
CN8 Right Angle Pin Header 8Way
H1B H1A
H15B H15A
H9B H9A
H4A H4B H3A H3B H2A H2B
-50V P
H5A H5B
H8A H8B
+50V P
H7B H7A
H1BH1A H2BH2A
H3BH3A
H4BH4A
H5BH5A
H6B H7BH7A
H8BH8A
H6B
1
2 3
4
5
6
7 8
CN3
Right Angle Pin Header 8Way
1
2
3
4
5
6
7
8
CN9
Right Angle Pin Header 8Way
H9B
H9A
H10B
H10A
H11BH11A
H12B
H12A
H13BH13A
H14B
H15BH15A
H16B
H16A
H12A H12B
H11A H11B
H10A H10B
H13A
H13B
-50V. R
H14B
H16A H16B
Q31
MPSA42 NPN Signal Q30
MPSA92 PNP Signal
Q42
MPSA92
PNP Signal
Q39 MPSA92 PNP Signal
Q38
MPSA42 NPN Signal
Q43 MPSA42
NPN Signal
R116 1/8W Metal Film 2K2
R117 1/8W Metal Film
120K
R118
1/8W Metal Film
100R
Q44
MPSA42 NPN Signal
D31
1N4148
Signal Diode
R119 1/8W Metal Film 2K2
R120 120K
1/8W Metal Film
R121 1/8W Metal Film 100R
Q45
MPSA42 NPN Signal
D32 1N4148 Signal Diode
VI Output (R) VI Bottom Input (R) Amp Output (R) VI Top Input (R)
-45V (R) Amp Output (R) Clip Output (R) +45V (R)
VI Output (R)
VI Bottom Input (R) Amp Output (R)
VI Top Input (R) -45V (R) Amp Output (R) Clip Output (R) +45V (R)
Right Protection PCB Connector (B) Left Protection PCB Connector (A)
R123 1/8W Metal Film 47K R124 1/8W Metal Film 18K
Q46
MPSA92 PNP Signal
C3
Ceramic
4.7nF 50V
R125
1/8W Metal Film
47K
R126
1/8W Metal Film 18K
Q47
MPSA92 PNP Signal
C45
Ceramic
4.7nF 50V
R127 1/8W Metal Film
18K
Q48
MPSA92 PNP Signal
C72
Ceramic
4.7nF 50V
C67
10uF 63V Electrolytic
R128 1/8W Metal Film 47K
R129
1/8W Metal Film
47K
R130 1/8W Metal Film 47K
R131
1/8W Metal Film 47K
H8B
H16B
+50V. R
-50V. R
+50V P
-50V P
Q49
MPSA42 NPN Signal
DGND
R140
4K7
1/8W Metal Film
C65
Electrolytic
10uF 63V
C66 10uF 63V
Electrolytic
Right Protection PCB (Clipping) Left Protection PCB (Clipping)
Right Protection PCB (VI)Left Protection PCB (VI)
DC Detection
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Cambridge Audio 740A Specifications

General

Brand	Cambridge Audio
Model	740A
Category	Amplifier
Language	English