Zenith XBS344 Series, Руководство по обслуживанию

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3-16
Check power.
Check REC start “H” signal
of µ-COM.
Check IC501 Pin 19.
(Audio Swich 30)
Check the Vcc of IC801.
(Pins 3, 15, 32, 46)
Is Pin 30 of IC801 over
3.5V ?
Is the Head switching signal
IC801 Pin 39 O.K?
Check the connection at
P3D01 if good then
Replace IC801.
Check Ports of µ-COM.
Check A.MUTE port of
µ-COM (Pin High of
IC501).
Replace IC801.
Hi-Fi Playback.
No sound
Check the Hi-Fi Selection
Switch and the Tape quality.
Is the RF waveform at
IC801 Pin 23 over 3V
Vp-p?
Check the Contact point
of Audio Output.
Do Audio signals appear at
IC801 Pin 80(L-CH),
78 (R-CH)?
Is IC801 Pin 49(A.Mute)
“High”?
Check IC801 Pin 37(Data),
Pin 38(Clock).
A.
YES
NO
YES
NO
NO
NO
NO
7. Hi-Fi Circuit
YES
YES
YES
YES
YES
YES
NO
YES