VCR ELECTRICAL TROUBLESHOOTING GUIDE - Mari TV Elettronica

VCR ELECTRICAL TROUBLESHOOTING GUIDE
5. Hi-Fi CIRCUIT
5-1. No Sound(EE Mode)
No Sound.
YES
Check the TU
Audio of IC801 Pins2, 3.
NO
Check the IC401 Pins106, 107.
Check the DVD
Audio of IC801 Pins4, 5.
NO
Check the IC402 Pins14, 15.
Check the AV1
Audio of IC801 Pins6, 7.
NO
Check the Scart1 Jack.
(JK905 Scart1 Audio in Pin2, 6).
Check the AV2
Audio of IC801 Pins8, 9.
NO
Check the Scart2 Jack.
(JK905 Scart2 Audio in Pin2, 6).
Check the AV3
Audio of IC801 Pins10, 11.
NO
Check the front Jack.
YES
Check the Vcc
of IC801 Pins34, 40, IC901
Pins14, 30.
YES
NO
Check the Power 5.0V, 12V.
Check the IIC
Clock and DATA at IC801
Pins42, 43.
YES
Check the Audio
of IC801 Pins16, 17.
YES
Check the
IC401 Pins120, 121.
YES
Check the Digital Audio path between
IC401 and DVD Board.
NO
NO
NO
Check the IC501 Pins17, 18.
Replace IC801.
Check the Pcb Pattern between IC801
Pin16, 17 and IC401 Pins120, 121.
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VCR ELECTRICAL TROUBLESHOOTING GUIDE
5-2. Hi-Fi Playback
PB mode
YES
No Sound.
YES
Check the Vcc of
IC801 (Pins34, 40)
NO
Check Power 5.0V, 12V.
YES
Check the
Hi-Fi Selection switch.
(IC801 Pin41) and the
Tape quality.
NO
Check IC501 Pin26
(A.H/SW)
YES
Is the RF
Envelope at IC801 Pin44
over 2Vp-p
NO
YES
Check IC801
Pin42(Data), Pin43
(Clock)
NO
Check the parts of µ-COM
(IC501 Pins17, 18)
YES
Do Audio
Signals appear at
IC801 Pin16(L-CH),
17(R-CH)
NO
Check the Connection at
P3D01 Pins7, 9.
YES
Do Audio
Signals appear at IC901
Pins37, 38.
NO
Check the 2C
402 Pins14, 15.
NO
Check the DVD Board
Audio path
YES
YES
Check the IC901 Pins11, 12.
Do Audio Signals appear
at JK901, JK905
NO
Check the Jack
(JK901,JK905)
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