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DR- R504X
9. Fine
Focus
Offset Adjustment
(Adjustment
2)
•Objective
To optimize the DC offset voltage of the focus servo
circuit.
•Symptom when out of
The player does not focus in, sound broken and the RF
~ignal
is
dirty.
adjustment
•Measurement instru-
Connect the oscilloscope to
ment
connections
TP201 (CN601
),
Pin
I
(RF).
[Procedure]
[Settings]
20 mY/division
500 ns/division
AC mode
•
Player
state
Spindle rotation frequency
:
Normal
speed,
focus
ON,
spindle
ON,
tracking
ON
•Adjustment
location
YR6 (FE.
OFS)
•Disc
YEDS-7
1.
Move the pickup to midway across the disc
(R=35mm).
Spindle rotation frequency
: Normal speed,
focus ON, spindle
ON and tracking ON
put
the player
into
play
mode.
·
2. Adjust VR6 (FE. OFS) so that the eye pattern
ofTP20
l
(CN60l),
Pin I (RF) (the diamond shape at the
center
of the
RF
signal)
can be
seen
the most
clearly.
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Out of adjustment
Optimum adjustment
41
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