Service manual

6-12
VL-H870U
VL-H875U
VL-H890U
VL-H870U
VL-H875U
VL-H890U
7. VCO adjustment
Measuring point TL1802
Address 43
Mode VCR AV input
Adjusting method 1) AV input : NON Signal
2) Connect the frequency counter to TL1802, and adjust the frequency.
Adjustment standard 15.734kHz ± 100Hz
Remarks ———————
8. H-position adjustment
Measuring point TL1802
Address 44
Mode VCR AV input
Adjusting method 1) Input the white 100% signal as an AV input.
2) Connect the oscilloscope to TL1802, and adjust the pulse width.
Adjustment standard 3 type 2.8µsec/3.5 type 3.74µsec
± 0.15µsec
Remarks ———————
t
V
9. COMMON PULSE adjustment
Measuring point TL1818
Address 22
Mode VCR AV input
Adjusting method 1) Set the data of address 47 at the address 80.
2) Input the white 100% signal as an AV input.
3) Connect the oscilloscope to TL1818, and adjust the pulse width.
Adjustment standard 6.6Vp-p ± 0.1Vp-p
Remarks ———————
Measuring point LCD panel display surface
Address 45
Mode VCR AV input
Adjusting method 1) Input the white 40% signal as an AV input, and set data of address 47 at the address 80.
2) Set the illuminometer (TOPCON IM-3) on the LCD panel surface (do not allow entry of external light).
3) Connect the illuminometer to the oscilloscope.
4) Make an adjustment so as to minimize the ripple of output waveform.
Response time: 0.6 sec
5) Adjust again if longitudinal stripe appears evidently.
* Or set to the point where the black is settled deepest with the grey scale signal.
Adjustment standard Minimum
Remarks Make an adjustment after aging for 5 minutes or more.
10. COM-BIAS adjustment
12. Touch panel position detection adjustment
Measuring point LCD panel display area
Mode VCR AV input
Adjusting method 1) Enter the adjustment of touch panel adjustment mode. (TEST mode OE)
2) Press successively the two-points OSD indication cross-shaped (+) one by one
1 the left above→ 2 the right below (setting point) → 34 (as you pleases).
Set back the adjustment mode by fifth touch (5).
Note: As touch the two-points indication (+), display the blue (12) → the purple
(34), the case color a light blue is the adjustment "OK" and the red is the
adjustment "NG".
The touch (34) can check the adjustment with the tip of finger indiation.
11. W/B adjustment
Measuring point LCD panel display surface
Address 41, 42
Mode VCR AV input
Adjusting method 1) White fade signal input.
2) Adjust so as to get the same white screen as that of standard monitor. (Adjust again, visually checking as
stated in item 2.3.)
Adjustment standard Standard monitor
Remarks Make an adjustment after aging for 5 minutes or more.
+
+
1
2