Marantz 120 Service Manual

Page 2

TABLE OF CONTENTS

SECTION PAGE
Introduction ............................................................. 1
AMTuner ............. 1
FM Tuner ............................................................... 2
Scope Display Circuit ...................................................... 4
Scope Circuit Description ................................................... 5
Power Supply Circuit ...................................................... 5
Trouble Shooting of Oscilloscope Circuit ....................................... 5
Scope Display Alignment ................................................... 6
FM Tuning Display Alignment ............................................... 6
AM Alignment ........................................................... 7
FM Alignment ........................................................... 7
Stereo Separation Alignment ................................................ 7
Muting Circuit Alignment ................................................... 8
Voltage Conversion ....................................................... 8
Test Equipment Required for Servicing ........................................ 8
Parts List ............................................................... 19
Specifications ............................................................ 25

LIST OF ILLUSTRATIONS

FIGURE No PAGE
1 Remove the Terminal Cover ............................................. 9
2 Voltage Conversion Chart ............................................... 9
3 Dial Stringing ........................................................ 10
4. Front Panel Adjustment and Component Locations ........................... 11
5. Main Chassis Component Locations (Top View) ............................. 11
6 Rear Panel Adjustment and Component Locations ........................... 12
7 Main Chassis Component Locations (Bottom View) ........................... 12
8 FM Front End Assembly P100 Component Locations ......................... 13
9. AM Tuner Unit Assembly P150 Component Locations ........................ 13

10. FM lF Amplifier Assembly P200 Component Locations ....................... 14

11. MPX Stereo Decoding Amplifier Assembly P300 Component Locations ........... 14

12. FM Detector Assembly P500 Component Locations .......................... 15

13. FM Noise and DC Amplifier Assembly P550 Component Locations ............... 15

14. Pre-Amplifier and Power Supply Assembly P400 Component Locations ........... 16

15. Scope Display Assembly P900 Component Locations ......................... 16

16 Function Switch Assembly P700 Component Locations ....................... 17

17. Display Switch Assembly P800 Component Locations ......................... 17

18. Muting and DC Level Adjustment Assembly P850 Component Locations .......... 17

19. Schematic Diagram .................................................... 18