39
VC SA350/350W
VC-SA355
VC-SA550/550W
YES
YES
YES
NO
NO
NO
FLOW CHART NO.6 POWER TROUBLESHOOTING(6)
In case of output voltage at low level.
Check peripheral circuits IC902, IC921,
C933, R932, R929, R930 and R931.
The IC901, C913, R908, R909, R910 and R911 as
a result of check, if poor replace.
Check IC902 and peripheral circuits
pin(9) of IC901.
Replace IC901.
Check short-circuit or leak of T901.
Replace T901.
Check primary circuit and peripheral
circuit of Q901.
FLOW CHART NO.7 TIMER TROUBLESHOOTING
The flourescent display tube fails light up.
Is the supply voltage of 5V fed to pin(8)
of IC801?
Check STBY 5V line.
Is the supply negative voltage of -25V
fed to pin(1) of IC801?
Check negative voltage line(STBY
-25V) and power circuit.
Is the filament voltage applied
between (1)/(2) and (31)/(32) of the
fluorescent display tube?
Also negative voltage applied
between these pins and GND.
Check power circuit and peripheral
circuit of D952.
Does the fluorescent display tube
function?
Replace IC801.
Check for cracks on the fluorescent
display tube.
YES
YES
YES
YES
NO
NO
NO
NO
FLOW CHART NO.8 KEY CONTROL TROUBLESHOOTING(1)
Does the key switch make good
contact, when the cassette tape is
inserted?
Check switch contact.
Is there the function control voltage
inputted at pins (96),(97) and (98)
of IC701, when the jog shuttle ring
are activated?
Check peripheral circuit of pins(96),
(97) and (98) of IC701, and the jog
shuttle ring.
Replace IC701.
YES
NO
NO
YES
Key-in input is not received
<For jog shuttle mode
.>
SW1(Pin96)
SW3(Pin97)
SW4(Pin98)
SW2(GND)
TERMINAL
ANGLE
0
-10
-20
-30
-40
-50
-60
10
20
30
40
50
60
-52
-38
-15
15
38
52
TEST
TP802
CASSETTE
TP801
CASSETTE
KEY OFF
TP801
TEST
YP802
S809
SET
S810
CH(+)
S811
EJECT
S813
3.8V
4.4V
5.0V
SW 1/SW 2 INPUT VOLTAGE(V)
3.1V
2.5V
1.9V
1.2V
0.6V
POWER
S885
STOP
S886
FF
S887
REW
S884
PLAY
S883
PAUSE/STILL
S882
REC
S807
CH(-)
S810
MENU
KEY 0 IN
KEY 1 IN
FLOW CHART NO.9 KEY CONTROL TROUBLESHOOTING(2)
Does the key switch make good
contact, when the cassette tape is
inserted?
Check switch contact.
Is there the function control voltage
inputted at the pins(87) and (88) of
IC701, when the keys are activated?
Replace IC701.
Check peripheral circuit of pins(87)
and (88) of IC701, and the function
keys.
YES
NO
NO
YES
Key-in input is not received
<Except for jog shuttle mode
.>
