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DW - S114X
12. VCO free-run frequency verification
@ Objective
To verify the VCO free-run frequency is optimized.
@ Symptom when out of | No play and track search is inpossible.
adjustment
@ Measurement instru-
| Connect the foscilloscope to
@ Player state
Spindle rotation frequency : Normal
ment connections
TP202 (CN609) , pin 2
speed*Fourfold speed, focus ON,
(PLLCN)
spindle ON/tracking ON
[Settings]
0.1 V/division
@ Adjustment location
| L603 (VCO ADJ)
5 ms/division
DC mode
@ Disc
YEDS-7
[Procedure]
1. In the normal speed, focus ON, spindle ON and tracking ON state, verify the center value (center value which is the
thick portion of line) of waveform's DC elements at TP202 (CN609), pin 2 (PLLCN) is OV + 0.1V.
2. In the fourfold speed, focus ON, spindle ON and tracking ON state, verify the center value of waveform's DC elements
at TP202 (CN609), pin 2 (PLLCN) is OV + O.1V.
3. If the specified values cannot be obtained, perform the verification after adjusting the section "I. VCO free-run
frequency adjustment" again.
13. WBL Offset Adjustment
@ Objective
To optimize the DC offset voltage of the wobble amp.
@ Symptom when out of
|CD~-R
disc does not record and playback.
adjustment
e@ Measurement instru-
Connect the oscilloscope to
@ Player state
Spindle rotation frequency : Normal
ment connections
TP2 (CN 104), Pin $ (WBL).
speed, focus ON, spindle ON,
[This connection may be via a
tracking ON
high-pass filter
isos 0kQ).]
@ Adjustment location
| VRI (WBL. OFS)
[Procedure]
1. Move the pickup to the midway across the disc.
2. Set to the normal speed, focus ON, spindle ON and tracking ON state.
3. Adjust VRI (WBL. OFS) so that the amplitude of the waveform becomes minimum.
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