Sanyo HV-DX4EV, Service Manual

Page: 13 / 34

23
WAVEFORMS
22
TROUBLESHOOTING
E. No NORMAL AUDIO playback in record/playback mode(Check in REC mode)
No Normal Audio playback in
record/playback mode
Are there Audio signal at IC251
pin#4~9?
Is there recording signal at
IC251 pin#21?
Check Input LINE1 JACK.
Check Input LINE2 JACK.
Check ICD03(DVD).
Check signal flow circuit.
YES
NO
NO
NO
Signal at IC251 pin#21 is transferred to
IC301 pin#13,15,17?
Collect signal at C222 is about
70Vp-p at 70KHz?
Check IC251.
YES
YES
Check Q203.
NO
Check P201 pin#2, 4, 8 and A/C
HEAD.
YES
REC (H) BASE voltage at Q206
is 5V?
Check IC501 pin#45.
NO
YES
1. VIDEO
!
(IC301-70) 5Vp-p
1V/2msec/cm
REC
!
(IC301-70)5Vp-p
1V/2msec/cm
PLAY
@
(IC301-46) 520mVp-p
200mV/5usec/cm
REC
@
(IC301-46) 520mVp-p
200mV/5usec/cm
PLAY
# (IC301-43) 520mVp-p
100mV/5usec
REC
# (IC301-43) 520mVp-p
100mV/5usec
PLAY
$ (IC301-21) 600mVp-p
200mV/2msec/cm
PLAY(SP) VIDEO SW TRIG
$ (IC301-21) 350mVp-p
200mV/2msec/cm
PLAY(EP) VIDEO SW TRIG
% (IC301-67) 4.6Vp-p
2V/10usec/cm
REC/PLAY
% (IC301-67) 4.6Vp-p
2V/10usec/cm
PICTURE SEARCH
^ (IC301-65) 2.2Vp-p
500mV/5usec/cm
REC
^ (IC301-65) 2.2Vp-p
500mV/5usec/cm
PLAY
& (IC301-28) 450mVp-p
200mV/0.1usec/cm