Fisher 634 Service Manual
This is the 26 pages manual for Fisher 634 Service Manual.
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Extracted text from Fisher 634 Service Manual (Ocr-read)
Page 2
TABLE OF CONTENTS
Required Test Equipment ...........................................
Chassis Parts List ...........
Harmonic Distortion Test
Tuner Alignment Procedures
Tuner Schematic .........................
Tuner Board Layout ......................
Tuner Alignment Waveforms ......
Tuner Parts List ...........
Tuner lC Signal Flow
Tuner IC Description .............................................
CD-4 Alignment Procedures .......
CD-4 Demodulator Board Layout
CD-4 Demodulator Parts List ................................
CD-4 Demodulator Schematic
Preamplifier Schematic ......................
Preamplifier Parts List .........................
SO Decoder/Gain Control & Remote Control Unit Schematic ......................... 15
SO Decoder/Gain Control 8! Remote Control Unit Parts List . . . . .................... 16
Audio Control Amplifier Schematic .................. 13
Audio Control Amplifier Parts List ...... 16, 17
Filter Selector Board Schematic ..................... . . . . 17
Filter Selector Board Parts List ..................... 17
Audio Level Meter Board Schematic ........ 18
Audio Level Meter Board Parts List ---------------------- - - 18
Pre-Driver/Driver and Power Module Schematic -------------- 19
Pre-Driver/Driver and Power Module Parts List ------------- 19
Speaker Selector Switch Schematic ................................... . . . 2O
Speaker Selector Switch Parts List .................................. . . 20
Fuse Board Schematic 21
Fuse Board Parts List 21
Speaker Protection Board Schematic ..................... 22
Speaker Protection Board Parts List 22
Dial Lamp Board Schematic ........... . 23
Dial Lamp Board Parts List .............. 23
Power Supply Schematic ............ 24
Power Supply Parts List ............................................. 25
REQUIRED TEST EQUIPMENT
The following test equipment is required to completely test and align the
Tuner section and the CD-4 Demodulator section of the Receiver:
0 Line Voltage Autotransformer or Voltage 0 Four (4) Load Resistors, 8-ohms,250 Watts
Regulator (Minimum Rated)
0 AC DC Multimeter o Low-Distortion AM-FM Signal Generator
0 Accurately Calibrated AC Voltmeter o 10.7 MHz Sweep Generator, Fisher Model 3024
o Oscilloscope (Flat to 100 kHz Min.) or equivalent
- Low-Distortion Audio Oscillator o 455 kHz Sweep Generator, Fisher Model 3025
o Harmonic Distortion Analyzer or equivalent
0 CD-4 Generator (Fisher 3109 or equivalent) a Multiplex Generator, Fisher Model 1536 or equivalent
a Frequency Counter - Two 12) RCA Shorting Plugs
CAUTION. This precision high-fidelity instrument should be serviced only by qualified personnel,
' trained in the repair of transitorized equipment and printed circuitry.
© COPYRIGHT 1974 FISHER RADIO I AII Rights Reserved.
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