Zenith XBV 443, Service Manual

Page: 26 / 108

3-17
(3) Hi-Fi REC
Hi-Fi REC.
It is impossible to record Hi-Fi Audio
signal.
Check Vcc of IC801.
(Pins3, 5, 15, 32, 36, 46, 54)
YES
YES
Check IC801 Pin37(Data), Pin38(CLOCK).
YES
Do Audio signals appear at IC801 Pin6?
YES
Do Audio signals appear at IC301
Pin76(Normal Audio)?
YES
Do OSC signals appear at P3D02 pins4,5
(50Vp-p)
YES
YES
Check Power.
NO
Check ports of µ-CPM.
(IC501 Pins71, 72)
Check Audio input signal of IC801
Pin57(TU.A.), 7, 69(DVD.A.),
11, 73(AVI.A.), 9, 71(AV2.A.)
NO
Check C825, C306, R311, R312, R346.
Check REC OSC BLOCK
(FL301, Q301~Q305, Q308, Q309)
Is “High” IC501 Pin74 in REC mode.
NO
NO
NO