Tatung VL5A9DA, Service Manual

Page: 9 / 89

9
2. Clock adjustment
Set the Chroma at pattern 63 (cross-talk pattern) or WIN98/95 shut-down mode (dot-pattern).
Adjust until the vertical-shadow as wide as possible or no visible.
This function is adjust the PLL divider of ADC to generate an accurate pixel clock
Example : Hsyn = 31.5KHz
Pixel freq. = 25.175MHz (from VESA spec)
The Divider number is (N) = (Pixel freq. x 1000)/Hsyn
From this formula, we get the Divider number, if we fill this number in ADC register (divider register),
the PLL of ADC will generate a clock which have same period with above Pixel freq.(25.175MHz) the
accuracy of this clock will effect the size of screen.(this clock was called PIXEL-CLOCK)
3. Focus adjustment
Set the Chroma at pattern 63 (cross talk pattern) or WIN98/95 shut down mode (dot-pattern).
Adjust the horizontal interference as less as possible
This function is adjust the phase shift of PIXEL-CLOCK to acquire the right pixel data .
If the relationship of pixel data and pixel clock not so match, we can see the horizontal interference at
screen only at crosstalk pattern and dot pattern we can find this phenomena, other pattern the affect is very
light
4. H/V-Position adjustment
Set the Chroma at pattern 1 (crosshatch pattern) or WIN98/95 full-white pattern confirm above item 2 & 3
functions (clock & focus) was done well, if that 2 functions failed, the H/V position will be failed too.
Adjust the four edge until all four-edges are visible at the edge of screen.
5. MULTI-LANGUAGE function
There have 5 language for selection, press “MENU” to selected and confirm , press “ LEFT” or “ RIGHT”
to change the kind of language ( English , Deutch , Francais, Espanol, Italian)
6. Reset function
Clear each old status of auto-configuration and re-do auto-configuration ( for all mode)
This function also recall 7800 color-temperature , if the monitor status was in “ Factory-mode” this reset
function will clear Power-on counter ( backlight counter) too.
7. OSD-LOCK function
Press Left & Right key during switching on the monitor, the access to the OSD is locked, user only has
access to “ Contrast, Brightness, Auto-key “.
If the operator pressed the Left & Right during switching on the monitor again , the OSD is unlocked.
8. View Power-on counter and reset the Power-on counter( if not necessary , not suggest to entry factory
mode)
The Power-on counter was used to record how long the backlight of panel already working, the backlight
life time was guarantee minimal 25000 hours, the maintainer can check the record only in factory mode.
Press MENU button for 2 seconds along with plug-in AC power cord will be in factory mode, and the
OSD screen will located at
left top of panel but take cautions
don’t press icon “78” & “65”, if you
press 78/65 , your white-balance data will overlap with the new-one, and you must perform the white-
balance process again.
The result of counter was place at top of OSD, the maximal of record memory was 65000 hours, if exceed
65000 hours the counter will keep in 65000 hours until press “ RESET” at osd-menu in factory mode.
The “ RESET” function in factory mode will execute following function:
1. clear the Power-on counter to zero hours
2. clear old auto-configuration status for all mode , so the monitor will automatically re-do auto-config
when change to next mode or power on-off
4-3 FRONT PANEL CONTROL KNOBS
Power button : Press to switch on or switch off the monitor.
Auto button : to perform the automatic adjustment from CLOCK, FOCUS, H/V POSITION, but no affect the
color-temperature
Left/Right button : select function or do an adjustment.
MENU button : to activate the OSD window or to confirm the desired function