Focus Bias Adjustment - Pioneer pdr-w739 Service Manual

6.5.4 Focus Bias Adjustment

Test Point CN102 - pin 1 (RF)
Adjustment Point
Adjustment Value
Symptom when out of
adjustment
[Procedure]
(1) Press the SYNCHRO button in Stop mode.
Note: Make sure the unit is in Stop mode.
(2) Check that "OPT" disappears on the FL display.
(3) Press the AUTO SPACE button so that "CDR 04ff34∗∗" appears on the FL display.
(4) Press the FINALIZE button for focus-in.
(5) Press the PLAY/PAUSE 6 button for CAV-servo spindle kick.
(6) Press the PLAY/PAUSE 6 button to close the tracking servo, then set the unit to Playback mode.
(7) Adjust with the REC LEVEL knob until the above adjustment value to be reached is obtained.
Press the REC LEVEL knob to register the adjustment. Once the adjustment is registered with the REC LEVEL knob, " ERASE " on the
FL display will disappear.
(8) Press the STOP button to stop the unit.
RF
10 : 1
VC
10:1 probe
Note: Adjustment must be done around mid-radius on a disc.
SYNCHRO button, REC LEVEL knob
Adjust until RF jitter is minimal or that the eye pattern of the RF waveform is most open.
Sound broken, record characteristics deteriorate
Jitter Meter
or
Oscilloscope
PDR-W739
69