JVC OL-A200 Service Manual page 17

13. Trouble Shooting
ag
The turntable does not rotate.
Does 22-23
V DC appear at the
emitter of Q801?
(The tonearm should
be out of the
Q801 or Q802 is
defective, or D802 or
SW801 is shorted?
Replace tt
Does around 30-40
V OC appear at the
collector of Q801?
D801 is discon
nected, or the
transformer is open.
Does 22:23 V
appear between powor
supply line sockets 1
and 2 on the motor
board ?
Check the wires for
disconnection and the
sockets for
looseness. tf any 1s
defective, replace it
IC1 on the MC9548
motor board is defec
tive. Check Q12 and
Q13
Is the voltage
at TP-4 around 0.3 V?
The turntable rotates at high speed.
Does a sinewave of
0:3 Vp-p appear
at TP.3?
Does the turntable
stop by grounding
TP-4?
IC1 is defective. Or,
check C7, R16 and
R15 for discunnec
tion
Does the
turntable stop by
shoting between the
base and emitter
of Q9?
Q10 is defective.
Replace it.
When the turntable
stops by connecting
the emitters of O5
and Q6 to —-12V,
QQ is defective
5 mVp-p appear
between TP 1 and
TP-2 when observed
on an oscilloscope?
IC1 1s defective. Or,
check R18 far
disconnection, etc
Does the turntable
rotate by shorung
between the collector
and emitter of
Q10?
Q10 ts detective
Replace it.
The turntable RPM is abnormal
No
Check the motor
FG pattern, etc.
R3.R8, RS or R6 ts
disconnected. Or,
check the Hall collec
tor and emitter of
Does
the turntable
rotate by shorting
between the
collector and
emitter of Q9?
short, etc.
QQ is defective
Or, check C7 for
Check the
following and replace
the defective parts.
C6. C7, R13, R14
are shorted
or opened?
Fig. 34
QL-A200
No, 2649