C.E.C. 530CD - Page 12

ADJUSTMENT PROCEDURES ccontinuea)
Jig
Adjusting Hole
6. Even if the phase difference is 180° in the above step, the E
and F beams may be mistakenly on two different beam pit
lines as shown below.
Main
Be sure that the E and F beams are in the same pit line for
subsequent adjustments.
7. Remove the short between test pin TROFF and GND, and
TP17 and TP18, and play back the fourth selection on
YEDS4.
8. Observe the waveform of the signal between test pin E and
test pin F using the dualtrace oscilloscope (Monitored in
ALT mode). The beam E and beam F are in the same pit line if
the trigger of waveform F is approximately 25us behind the
point (Position where waveform hollows out) where the
waveform E is triggered.
The two beam are on the same pit line.
(100mV/DIV : 54Sec/DIV)
When observation of the waveform is difficult, the trigger
level can be varied. When the beams are not in the same line,
return to step 1, and rotate the adjustment jig at the 180°
point. Confirm that the beams are in line at the 180° point.
Repeat steps 1 to 7 until confirmation of this is possible.
Note:
When the pick-up is replaced, it is adjusted as a unit, and
beams E and F can be brought in line and the phase made |;
180° by a slight adjustment. Slightly rotate the adjustment |
jig when making adjustment. If the beams come out of line, it
is difficult to bring them back into the same pit line.
ADJUSTMENT OF PICK-UP ANGLE
1. Remove the table load.
2. Directly mount test disk YEDS4 on the turntable.
3. Turnon the power and playback the fourth selection.
4. Connect the oscilloscope between test pin HF (TP1) of
connector CNQ and test pin GND. Monitor the waveform of
HF (TP1) and rotate the angle adjustment screw so that the
waveform is at its maximum.
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