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PD-S703
3. Pickup Radial/Tangential Tilt Adjustment
@ Objective
To adjust the angle of the pickup relative to the disc so that the laser beams are shone straight
down into the disc for the best read out of the RF signals.
@ Symptom when out of | Sound broken;some discs can be played but not others.
adjustment
@ Measurement instru-
| Connect the oscilloscope to
@ Player state
Test mode, play
ment connections
TPH, Pin 1 (RF).
@ Adjustment location
| Pickup radial tilt adjustment screw
[Settings]
20 mV/division
and tangential tilt adjustment screw
200 ns/division
AC mode
YEDS-7
[Procedure]
1. Press the
TRACK /MANUAL SEARCH FWD PP - bl or REVI<k1-« <k) key to move the pickup to halfway across
the disc (R=35mm).
Press the OUTPUT SELECTOR key, the PLAY [> key, then the PAUSE [][] key in that order to close the respective
servos and put the player into play mode.
. First, adjust the radial tilt adjustment screw with a Phillips screwdriver so that the eye pattern (the diamond shape at
the center of the RF signal) can be seen the most clearly.
. Next, adjust the tangential tilt adjustment screw with a Phillips screwdriver so that the eye pattern (the diamond shape
at the center of the RF signal) can be seen the most clearly (Figure 3).
. Adjust the radial tilt adjustment screw and the tangential tilt adjustment screw again so that the eye pattern can be
seen the most clearly. As necessary, adjust the two screws alternately so that the eye pattern can be seen the most
clearly.
. When the adjustment is completed, lock the radial and tangential adjustment screw.
Note:Radial and tangential mean the directions relative to the disc shown in Figure 2.
Phillips
screwdriver
Radial direction
Tangential direction
;
za
te
a
its
peter
vt
a
irection
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yw
Ye
:
:
Et
et
Radial direction
Disc
Figure 2
Adjustment locations
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