Technics QUARTZ SP-15 - Page 12

(C)
Speed changeover is defective.
(D) Pitch control is defective,
causing uneven rotation
Check speed setting circuit.
1C303, 304
1C303 voltage $302 ~ 304
1C304 voltage
(Refer to the reference voltage
for each IC terminal.)
BAD
Check crystal-controlled oscillator
power supply.
TP35 - 9V
D315
Check VCO power supply. BAD
TP39 - 4.8V
D316
BAD
X301
Check crystal-controlled oscillator
1C304
circuit. 3.8ms
4.2V
TP37
ico voltage
(Refer to the reference voltage
for each IC terminal.)
Check
pitch
control
circuit
1C305
1C305
voltage
Q302
~
304
(Refer
to
the
reference
voltage
for each IC terminal.)
Q302 ~ Q304 voltages
(Refer to schematic diagram. )