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3-7. RF Gain t NG (Judgment is not performed.)
3-8. RF Jitter Check t NG
4. Write (CDR) Adjust
4-1. Jump Adjust t NG
4-2. Adjust WFB t NG (Judgment is not performed.)
4-3. ATER (Absolute Time in pre-groove Error Rate) Check t NG
4-4. Focus Bias ATIP (Absolute Time In Pre-groove) t NG (Judgment is not performed.)
Purpose
Coarse RF gain adjustment of the
OP unit for the CD. It prevents the
OP unit from mis-recognition of
the RF signal for the CD.
Trouble Symptom
OK is shown all the time. The OK/
NG judgment is not performed.
Cause Repair
Purpose
Measurement of the CD jitter
caused by the OP unit
Trouble Symptom
The measurement value of the
jitter meter for the RF jitter of the
CD does not show the value of 8
ns or less.
Cause
If the defective RF jitter is found
as the result of trouble analysis,
the OP actuator is distorted as it
is dropped causing skew. If the
defective RF jitter is found after
replacement of the OP unit, the
skew adjustment is incomplete.
Repair
Readjust the OP unit starting from
the skew adjustment. If readjust-
ment cannot produce satisfactory
result, go to section “4-6. Self RF
Jitter” of CD- R. If section “4-6.
Self RF Jitter” shows the good
result, there is no problem.
Purpose
Adjustment of the jump address
of the OP unit and adjust for
minimum overrun of the OP unit.
Trouble Symptom
NG indication appears.
Cause
Convergence after jump cannot be
obtained within the specified time
even though the sled offset is
changed at the jump of the slid
profile system. Convergence after
jump cannot be obtained within
the specified time even though the
kick voltage is adjusted at the
jump of the 2N type.
Repair
When a proper combination of the
OP unit and the circuit board is
selected after the OP unit is re-
placed, the satisfactory result can
be obtained. The replaced OP unit
or the board can be re-used.
Purpose
Check non-uniformity of the write
focus bias of the OP unit.
Trouble Symptom
OK is shown all the time. The OK/
NG judgment is not performed.
Cause Repair
Purpose
Measures the number of the ATIP
errors that have occurred during
writing.
Trouble Symptom
NG indication appears.
Cause
Error rate has exceeded the speci-
fications. (There can be a case that
disc is dirty.)
Repair
Check if the disc is dirty or not. If
disc is found dirty, clean and re-
adjust the parts. If not replace the
OP unit.
Purpose
Performs the fine adjustment of
read-out focus and the measure-
ment by self recording and play-
back.
Trouble Symptom
OK is shown all the time. The OK/
NG judgment is not performed.
Cause Repair
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