Aiwa XP-V320, Руководство по обслуживанию

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The servo circuit of this model has been designed to be free of adjustments and controlled within the IC. Therefore, adjustments and disk judgement
are performed automatically every time the TOC is read out. The adjustment status of each servo inside the IC can be monitored in this test mode.
1. Startup procedure
1) Short the test land.
2) Insert the AC plug.
3) Press the STOP button. (The test mode starts.)
Note 1) The test mode is canceled by disconnecting the AC plug.
Note 2) The OPEN/CLOSE switch cannot be operated during the test mode.
2. Checking the RF level
Test point: RF & VC (Vref)
Test disk: TCD-782
Play back the disk and confirm that the RF waveform is in the following state:
VOLT/DIV:200mV
TIME/DIV:0.5us
3. Checking each servo
The adjustment values of each servo can be checked by pressing the MODE button repeatedly during playback. The switching
procedure is as follows.
Check mode OFF
™
Vref offset (RO)
™
focus offset (FO)
™
tracking offset (TO)
™
tracking balance (TB)
™
tracking gain (TG)
™
focus gain (FG)
™
focus bias (FB)
™
check mode OFF
Example: Tracking offset (TO) Adjustment value ™ F5
* Adjustment values are indicated in hexadecimal.
When displaying each mode on the LCD and pressing the PLAY button in the STOP status, the center value is displayed on the LCD.
After the disk starts rotating, the adjustment value that was set during automatic adjustment is displayed. The display range of the
center values and adjustment values of each mode are as follows. There are 256 steps for displaying the values of all modes.
0.8Vp-p or more
RNDM RESUME
DSL
1
Tracking offset Adjustment value
Center value
1) Vref offset (RO)
2) Focus offset (FO)
3) Tracking offset (TO)
4) Tracking balance (TB)
5) Tracking gain (TG)
6) Focus gain (FG)
7) Focus bias (FB)
Center value
00
00
00
80
40
40
00
Display range
80-7F
80-7F
80-7F
00-FF
00-FF
00-FF
80-7F
TEST MODE-2/3