Focus/Tracking Gain Adjustment; Primary Adjustment - Sony CFD-K10 Service Manual

CFD.KlO
ENC
Focus/Tracking Gain Adjustment
A frequency responce 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 shock
when the 2-axis device operate.
However, as these reciprocate, the adjustment is at the Doint
where both are satisfied.
r When gain is raised, the noise when the 2-axis device
operates increases.
oWhen gain is lowered, mechanical shock and skipping
occurs more easily.
The following is a simple adjustment method.
- Primary Adjustment -
Note: Since exact adjustment cannot be performed, remem-
ber the positions of the controls before performing the
adjustment.
If the positions after the primary adjustment are only
a little different, return the controls to the original
Dosition.
Keep the set horizontal.
If the set is not horizontal, this adjustment cannot be\
performed due to the gravity against the 2-axis device.
/
Connect oscilloscope to TP701 pin O (VREF) and pin @
Procedure :
audio'CD
board
T P 7 0 l
oscilloscope
(dc range)
(FE-t) on audio-CD board.
3. Insert disc (YEDS-I8) and press D PLAy button.
4. Adjustment RV702 on audio.CD board so that the
waveform is as shown in the figure below. (focus gain
adjustment)
. Incorrent Examples (DC level changes more than on adjust-
ed waveform)
low tocus gain
VOLTIDIV : 1O0mV
TIME/DtV : 2nS
VOL||D|V : loonv
TIME/Dlv : 2mS
VOLT lDlV : lo1nv
TIME/DlV: 2mS
l 0 O m V
75mV
O V
. When gain adjustment is off, the symptoms below appear.
Gain
Symptoms
Focus Tracking
. The time until music starts
becomes longer for STOP --D
PLAY or automatic selection.
(K<, >> buttons pressed.)
(Normally takes about 1 sec-
onds.)
low
low or high
r Music does not start and disc
continues to rotate for STOP
--D PLAY or automatic selec.
tion.
(K<, >)| buttons pressed.)
low
r Sound is interrupted during
PLAY. Or time counter display
stops progressing.
low
. More noise during 2-axis
device operation.
high high
high locus gain