Fisher CA 857 Service Manual

Page 1

SERVICE MANUAL FISHERE

INTEG RATE D
STEREO AMPLIFIER ( ;A_85 7
(U.S.A.)
1 32 31 1 22
SPECIFICATIO NS
_ POWER AMPLIFIER SECTION Graphic Equalizer
Minimum RMS sine wave power perchannel 63 Hz t10dB
within stated bandwidth at no more than stated 250 Hz :10 dB
distortion and with 8-ohm load 100 Watts 1 kHz :10 dB
Power Bandwidth 20 Hz - 20 kHz 4 kHz :10 dB
Total Harmonic Distortion 0.09 % 16 kHz $10 dB
l.M. Distortion 0.09 % Loudness Contour (1 00 Hz/10 kHz) +8 dB/ +4 dB
Speaker Damping > 20 Hum & Noise (IHF Short Circuit, A Network)
PREAMPLIFIER SECTION Phono 65 dB
Frequency Response -. Tape Monitor 85 dB
Phono (RIAA) v :1 dB Tuner/Video/Aux/CD 85 dB
Video/Aux (20 Hz - 20 kHz) +1 dB GENERAL \
input Sensitivity and impedance Power Requirements (50/60 Hz) 120 VAC :10 %
Phono 2.5 mV/50 k0 Power Consumption 470 Watts
Tape Monitor 150 mV/SO kn AC Outlets 1
Tuner/Video/Aux/CD 150 mV/50 k0 Dimensions (W x H x D) 17.33 x 4.25 x 12.4
Phono Max: Input Capability 150 mV Weight (approx) 16.5 lbs.

- Specifications are subject to change without notice.-

WM-1 7782

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CONTENTS

Functional Block Diagram ....................................................................... 2
Cabinet & Chassis Exploded View ............................................................ 3,4
Cabinet & Chassis Parts List .................................................................... 5
Power Amplifier Adjustment ..................................................................... 6
Integrated Circuit Block Diagram ............................................................. 6,7
P.C.Board Parts List .................................................................... 8,9,10,1 1
Printed Circuit Board (Bottom View) .. .. 12,13,14
Point to Point Wiring Diagram 15,16
Schematic Diagram ......... .. . 17,18
Semiconductor Lead Identification ............................................................ 19 -

FUNCTIONAL BLOCK DIAGRAM

FUNCTION TAPE Graphic 50. Amp.
E0. Amp. 0N MONITOR Pre Amp,

PHONO @-> : ---oi;

ON 0--
TUNER ©---.-o° OFF Graphic ea. VR.
ON 0-.
co @-.-<\°
OFF

0

TAPE

AUX N °--' PLAY BACK Meter Drive IO M power
VIDEO © 0 OFF ® Level Meter
TAPE © .-

REC. OUT

Speaker
System
BALANCE VOLUME A
Power Amp, Speaker
Selector
-d\9
Protector °_ 8
I Protector Fuse
ON

Circuit
OFF -wv-v
nigm
LOUDNESS Channel Headphone