Teac PD-135 - Page 12

6
Main P.C.B. :
CN2 “3
2
t
Tracking Gain:
Focus Gain} ~. e4
6 ee ae
Pick-up
CN2 3
2
1
ADJUSTMENT
PROCEDURES
ccontinuea)
5 Signal
Generator
10K 0047 —
10K 0.0047
i Dualtrace
Oscilloscope
@ Remove connector CN2 from the pick-up and connect the
measurement circuit between the PCB and pick-up.
e@ The IC used is TA7256P
e VR contro! 2k0-B shorts IN and SG, 1kHz 1Vp-p is supplied
from the signal generator, and adjustment is made for
minimum output from OUT.
Precise adjustment procedure
1.
Focus gain adjustment
Connect the measurement circuit shown above, turn on the
power, and mount the test disk YEDS4.
Playback the first selection on the test disk, and apply a 950 Hz
0.5Vp-p signal from the signal generator.
. Observe the resurge waveforms on the oscilloscipe, and adjust
P103 so that the phase difference of outputs X and Y from the
measurement circuit is 90°.
-/Jj-
Tracking gain adjustment
. Adjustment is made in the same manner as for focus gain.
The input from the frequency generator is set to 950Hz 0.5Vp-p,
and P104 is adjusted so that the phase difference is 90°.