Sony CDP-CX235 - RFO Level Check

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CH 1 1.00 V= STO P
CH 2! 500mV= M TB1.00m s PK D ch1+
2
Normal
Tracking
error
waveform
Traverse
waveform
0.5V/div
0.5V/div
Vc
Vc
13. The Traverse waveform should be no smaller than 0.7Vp-p.
14. Measure the DC voltage from the Vc reference to the center of the
waveform (offset voltage). As the optical assembly ages, these two
will not be the same.
______________
In this example Vc is the same point as the center of the waveform so
step 14 = 0Vdc offset.
15. Divide the offset voltage measured in step 14 by the waveform’s Vp-
p. and multiply by 100. The result must be less than 22%
Offset DC voltage / Traverse Wave Vp-p X 100 = imbalance %
16. In our example, the waveform is 1.2Vp-p. Dividing 0/1.2V = 0% which
is less than 22%
17. Press the GROUP 8 button to restore the tracking servo and examine
the normal tracking waveform.
18. Measure the TE waveform DC offset voltage. It must be almost the
same as the offset measured in step 13. If not, there is metal fatigue
in the lens supports of the optical assembly (defective).
RFO Level Check
The RFO level must be at least 1Vp-p.
Move the scope probe to the RFO test point on the same BD board.
While the disc is playing, the output level should be at least 1Vp-p (spec is
1.2Vp-p).