Technics SL-1200MK2

ADJUSTMENT (Electrical)
Adjustments (Electrical)
Notes : 9 Make the following adjustments after replacing parts such as IC's, transistors, diodes, etc .
Condition of the set .
1 .
Power switch
.
. . . . . . . . . . . .
ON
2 . Pitch control
.
. . . . . . . . . . . . Center position
3 . Speed
selector switch
. . . . . . . 33-1/3
r .p .m .
Instruments to be used
1 . Tester
2 . Frequency counter
REFERENCE VOLTAGE
AND WAVEFORM ATEACH IC
PIN
IC101 (AN6675)
SL-1200MK2
SL-12
Q2
C
(D
O
OO
Adjustment Connection Points Adjustment Point
Adjustment Method
Adjustment
of pitch
Frequency counter 1 . Pitch control switch to center position .
A control t0%
(2) - . TP27 VR301 2 . Adjust VR301 for 262 .08 kHz
10 .05
kHz
of
(PITCH)
0
-
GROUND frequency .
Adjustment Tester
B
of
pitch
TP31 and VR302
Adjust VR302 for 2 .7 k92 t0 .1 of resistance
control gain TP32
value
Braking
Adjust VR201 for complete stop within 120 ° - 270°
C adjustment - VR201 after stop signal initiated
. (Turntable becomes free a
(BRAKE) few seconds after stop)
STOP
SIGNAL
2700
&1
Turntable
0
Start
Stop
Start Stop Start Stop
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