Service manual

-53-
TROUBLESHOOTING GUIDE
3-7) NO RECORD SOUND
Check the waveform of ICY01 #74
NG : GO to the figure
2-2 (TV PART)
OK : GO to the figure n
ICY01
VCR Y/C
LA71076AM
XS01
32KHz
Check
the crystal
Check
the voltage
ICS01
TIMER/
SYSCON
#2
0
#70
XS02
16MHz
#3
5
#3
6
#38
#39
#3
7
#3
4
RESET
Vcc(5V)
#9
8
#99
Vcc(5V)
Vcc(5V)
Check
the voltage
(5V)
PB L
REC H
Check
the crystal
#1
1
#17
Check
SCL/SDA signal
2
#8
7
#75
A Vcc
HA Vcc
#1
2
#26
AUDIO
HEAD
Invert REC H
from ICS01#20
REC H,PB L
#98
#96
AUTO
BIAS
#6
Check
the voltage
H : QUE/REV/STILL
L : NORMAL PLAY
A.MUTE
#7
#99
Check
the waveform
3 6
4
#4
AUDIO
ERASE
HEAD
FULL
ERASE
HEAD
Check
the waveform
70KHz
If SINE wave no signal,
then change TU01
TU01
70V
n
Appendix