Service manual

37
VL-Z1U
2. Adjustment of DAC full scale (Main PWB)
Measurement point TL6807(G OUT) Address VCR ADJ 094(G)
Mode VCR AV input
Adjusting method 1) Set the data values at addresses 41E/086/41C and 410 to FF/80/77 and 00, respectively.
(The LED shows nothing.)
2) Set the data values at addresses 096/411 and 0A8 to 00/80 and 48, respectively.
3) Connect the digital voltmeter to TL6807 (G_OUT) and measure the DC voltage.
* The measured voltage is (DA_VG).
4) Set the data values at addresses 096 and 411 to 80 and 00, respectively.
5) At address 094, adjust the DC voltage to the adjustment rating.
6)
Preset the data values at addresses 093 and 095 so that they are the same as the data value at address 094.
7) Reset the data at addresses 41E/086/096/41C/411/0A8 and 410. (Initial value: 00/C5/28/7F/28/
42 and 7D)
Adjustment rating DA_VG + 0.35V ± 10mV
Examples · Replacement of IC705, IC4401
4. Adjustment of LCD_ contrast (LCD PWB)
Measurement point TL846(LCD_VG) Address VCR ADJ 7C3
Test signel 0.900V
Procedure 1) Set the data value at address 41E (GRYLEV) to BE. (100% white display)
2) Set the data value at address 41C (TESTSW2) to 77. (1H inverted STOP)
3) Connect the digital voltmeter to TL846 (LCD_VG), and at address 7C3 (CONTRAST), adjust the
DC voltage to the adjustment rating.
Adjustment rating ± 50mV
Examples · Replacement of IC801, IC800
5. Adjustment of COM-Bias (with the unit settings complete)
Measurement point LCD panel display surface Address VCR ADJ 7C9
Mode VCR AV input
Adjusting method 1) Apply a 40% white signal to the AV input.
2) Set the illuminometer (TOPCON IM-3) on the LCD panel surface. (Cut off outside light.)
3) Minimize the ripple of the output waveform of the illuminometer.
Adjustment rating Minimum value
Remarks Make adjustment after five minutes or more of aging.
Examples · Replacement of LCD panel · Replacement of IC800
6. Adjustment of W/B (with the unit settings complete)
Measurement point LCD panel display surface Address VCR ADJ 41F, VCR ADJ 421
Mode VCR AV input
Adjusting method 1) Apply a 40% white signal to the AV input.
2) Apply a 40% white signal to the standard monitor. Make adjustment so that the image on the LCD
becomes equivalent to the image on the standard monitor.
Remark Standard monitor
Examples · Replacement of LCD panel · Replacement of IC4401, IC705
Response time: 0.6 sec
3. Setteing of parameters (LCD PWB)
* Preset the following data.
Address 7C0 7C6 7C7 7CB
NTSC 49 00 40 40
PAL 49 00 40 40