Philips VAD8041, Руководство по обслуживанию

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Alignments, Test Procedures EN 31 VAD8041 8.
8. Alignments, Test Procedures
8.1 Adjust Laser Control
In case of exchanging DVD-M or PWB an adjustment to align
OPU and PWB to each other is necessary.
8.1.1 Adjustment Procedure
– Connect the Digital Board to a PC via serial cable (3122
785 90017)
– Start up Hyperterminal or any other terminal program with
the correct settings (19200 8-N-1)
– Power on the set
– Call up nucleus 931 of the DSW. The adjustment takes
about 30 seconds
Example:
DS:> 931
93100
Test OK @
– Now data within the OPU EEPROM and the FLASH of the
PWB are aligned.
8.2 Drive Test
8.2.1 Short Term Test Procedure
Test 1: Disc LVP 12.01 (7104 099 91731) test layer change on
track 28 ->31
Duration: 1 minute
When the LVP12.01 disc is loaded and accepted the next steps
are:
–
Skip to track 29.
– Press next to chapter 30.
– Fast forward to halfway track 30
– Play track 30 till track 31 halfway
– When this part of the disc is played without any still pictures
or freeze frames the beamlanding of the OPU is good (the
track transition at the beginning of track 31 gives a short
still picture but this is normal.)
– Stop the disc.
Test 2: DVD+R blank disc type Ricoh 4X (7104 099 94261)
Duration: 4 minutes
– Record 1 minute
– Press stop
– Open / close
– Play back recorded track
Remark: When this disc is used for 30 recordings the disc
appears to be full. But physically the disc is not full and to use
also the remaining space on the disc you can do this by
deleting the index pictures.
Test 3: CD-RW low reflection audio disc. (7104 099 96581)
Duration: 1 minute
– Play a few seconds from track 1
– Skip to the last track
– Play a few seconds of the last track.
– Stop the disc
8.2.2 Long Term Test Procedure
Following the steps to be taken for all DVD recorders coming in
for service to the workshop related to a DVDM failure and which
have “No Defect Found”, NDF after a Short Term Test.
In case no defect is found during the “Short Term Test
Procedure” the test has to be extended with a burn in test -
“Long Term Test Procedure”.
The burn in test described herein should be done with a
DVD+RW disc.
Make a recording of 1 to 2 hours on M1/HQ and M2/SP mode.
Remark:
Attention! To prevent scratches the discs should be treated
very carefully!
Heavily scratched discs have a bad influence on the test
performance and should be replaced.
The technician has to decide by visual inspection the reliability
of his test material.
The pictures below show a bad example of discs used too long.
Figure 8-1
Figure 8-2