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*
Except when
checking voltage, disconnect
the Power cord before repair without
fail.
TROUBLE
CAUSE
|
Turntable Speed
:
Remove
back cover
and, using DC volt-
A. Switching
on
does
not
cause
meter, check printed base voltage:
turntable to rotate.
1. No output
of constant-voltage circuit
(between Tr1 collector and 4) is found.
(1) No output on secondary of transformer.
*
Cord disconnected.
*
Soldered improperly.
Fuse disconnected.
*
Power transformer defective.
(2) Output
found
on secondary of trans-
former.
*
Constant-voltage
circuit
parts
(ZD1),
Tri, Tr2) defective.
2.
Output
of
constant-voltage
circuit
is
17~20V.
*
3-phase switching circuit (Tr4 ~Tr9),
oscillator circuit (Tr3) defective.
Tr14 defective.
Power Switch is not ON.
Micro switch defective.
Speed selector switch defective.
Contact faulty
Soldered imProperly.
REMEDY
Replace cord.
Solder securely.
Replace fuse.
Replace power transformer.
x *£ *k *
*
Replace printed base assembly.
*
Replace printed base assembly.
*
Replace micro switch.
*
Replace speed selector switch.
*
Solder securely.
* * Dh *
W
= °
Constant-voltage output is not 17~20V.
Constant-voltage
circuit
parts
(ZD1,
Tr1, Tr2) defective.
Constant-voltage output is 17V~20V.
Diodes D8, DY, ZD2 defective.
Diodes D5, D6, D7 shorted.
Speed maladjusted.
B. Turntable speed too fast.
*
Replace printed base assembly.
Replace printed base assembly.
Replace motor.
(Stater frame Ass''y).
Adjust semi-fixed resistor VR1 & VR2.
* * KA
. Constant-voltage output is not 17~20V.
*
Constant-voltage parts (ZD1, Tr1, Tr2,
defective.)
2. Constant-voltage output is 17~20V.
*
Diodes D8, DY, ZD2 defective.
*
Speed unadjusted.
. Turntable speed too slow.
Replace printed base assembly.
Replace printed base assembly.
*
Adjust semi-fixed resistor VR1 & VR2.
will stop soon.
Replace selector switch.
Replace lead, or solder securely.
Replace printed base assembly.
Selector switch defective.
Lead disconnected or unsoldered.
Contact of Vr1, Vr2 insufficient.
. Operative
at
only
one
of
two
speeds.
(33-1/3 rpm, 45 rom)
Make it become
50mV
at both ends
of C15 with semi-fixed resistor VR3.
*
Make
it become
2.2V at both ends
of R38 with semi-fixed resistor VR4.
*
Semi-fixed
resistor
VR3
&
VR4
unadjusted.
. When
actuating,
turntable
speed
is unsteadly for along time.
*
Power
transformer
makes loud
noise
*
Replace
power
transformer.
of vibration.
*
Broken
part of rotor
magnet
of iron
chips attracted by magnet and rubbed
by motor case.
Noise
Offensive noise is hears.
Remove iron chips.
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