Zenith DVB318, Service Manual

Page: 31 / 68

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CIRCUIT DIAGRAM
1. POWER(SMPS) CIRCUIT DIAGRAM
IMPORTANT SAFETY NOTICE
WHEN SERVICING THIS CHASSIS, UNDER NO CIR-
CUMSTANCES SHOULD THE ORIGINAL DESIGN BE
MODIFIED OR ALTERED WITHOUT PERMISSION
FROM THE ZENITH ELECTRONICS CORPORATION.
ALL COMPONENTS SHOULD BE REPLACED ONLY
WITH TYPES IDENTICAL TO THOSE IN THE ORIGI-
NAL CIRCUIT. SPECIAL COMPONENTS ARE SHADED
ON THE SCHEMATIC FOR EASY IDENTIFICATION.
THIS CIRCUIT DIAGRAM MAY OCCASIONALLY DIF-
FER FROM THE ACTUAL CIRCUIT USED. THIS WAY,
IMPLEMENTATION OF THE LATEST SAFETY AND
PERFORMANCE IMPROVEMENT CHANGES INTO
THE SET IS NOT DELAYED UNTIL THE NEW SERVICE
LITERATURE IS PRINTED.
NOTE :
1. Shaded( ) parts are critical for safety. Replace only
with specified part number.
2. Voltages are DC-measured with a digital voltmeter
during Play mode.
NOTES) Warning
NOTES) Parts that are shaded are critical
NOTES) With respect to risk of fire or
NOTES) electricial shock.
NOTES : Symbol denotes AC ground.
Symbol denotes DC chassis ground.
Power Control is abnormal
Power dead
Current feedback IC
-27VA is abnormal
VF+ not output
3.3V output is abnormal
Power dead
High Speed S/W IC
12V output is abnormal
3.3V output is abnormal
DV7832NXS