SONY SAWM20
Service Manual

SA-WM20 SECTION 1 GENERAL
� Location of controls � Front view (a part) �

SECTION 2 DIAGRAMS
THIS NOTE IS COMMON FOR PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS. (In addition to this, the necessary note is printed in each block.)

For printed wiring boards.
Note: � X : parts extracted from the component side. � Y : parts extracted from the conductor side. � b : Pattern from the side which enables seeing.

For schematic diagrams.
Note: � All capacitors are in µF unless otherwise noted. pF: µµF 50 WV or less are not indicated except for electrolytics and tantalums. � All resistors are in � and 1/4 W or less unless otherwise specified. � C : panel designation. Note: The components identified by mark 0 or dotted line with mark 0 are critical for safety. Replace only with part number specified. Note: Les composants identifiés par une marque 0 sont critiques pour la sécurité. Ne les remplacer que par une piéce por tant le numéro spécifié.

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1 POWER (@/1) button 2 POWER indicator 3 PHASE (4 NORMAL/$ REVERSE) button 4 CUT OFF FREQ dial 5 LEVEL dial

� : B+ Line. � : B� Line. � Voltages are dc with respect to ground under no-signal conditions. no mark : Power on � : Impossible to measure � Voltages are taken with a VOM (Input impedance 10M�). Voltage variations may be noted due to normal preduction tolerances. � Signal path. K : AUDIO � Abbreviation CND : Canadian model SP : Singapore model MX : Mexican model MY : Malaysia model

2-1. Circuit Boards Location

POWER IC board LED board

SWITCH board MAIN board

CONTROL board

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