Sony CFD-600 Service Manual page 45

Focus Bias Adjustment
This adjustment is to be done when the optical pick-up block
is replaced.
Procedure:
oscilloscope
(DC range)
RF (1C702@).
GND
CD board {
1. Connect the oscilloscope between RF and GND.
Insert disc (YEDS-18) and push the > [{] button.
3. Adjust RV701 so that the oscilloscope waveform is
maximum as shown in the figure below (eye pattern).
e RF signal reference waveform (eye pattern)
WKY LXLXLXLY)
VF
,
Wi XN
WARN
AYYYYYYY)
OV
When observing the eye pattern, set the oscilloscope for AC
range and raise vertical sensitivity.
Adjustment Location: See page 12.
Focus/Tracking Gain Adjustment
A frequency response analyzer is necessary in order to per-
form this adjustment exactly.
However, this gain has a margin, so even if it is slightly off,
there is no problem. Therefore, do not perform this adjust-
ment.
Focus/tracking gain determines the pick-up follow-up (ver-
tical and horizontal) relative to mechanical noise and me-
chanical shock when the 2-axis device operate.
However, as these reciprocate, the adjustment is at the point
where both are satisfied.
e When gain is raised, the noise when the 2-axis device
operates increases.
e@ When gain is lowered, it is more susceptible to mechanical
shock and skipping occurs more easily.
When gain adjustment is off, the symptoms below appear.
symptoms | Fee | Tsi
eThe time until music starts
becomes longer for Hi D> UJ on
automatic selection. low low or high
(K4< , PPI buttons pressed.) (Nor-
mally takes about 2 seconds.)
eMusic docs not start and disc
continues to rotate for M > > {][] (ag:
or automatic selection.
PLAY. Or time counter display low
stops progressing.
' : : — ;
More poise during 2-axis device
operation.
(Kk, PPI buttons pressed.)
eSound is interrupted during