Front Panel Control Knobs - Acer SPECTRUM AL801 Service Manual

2. Clock adjustment
Set the Chroma at pattern 63 (cross-talk pattern) or WIN98/95 shut-down mode (dot-pattern).
Adjust until the vertical-Stripe-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
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 will see the horizontal interference on
screen ,we only find this phenomena in crosstalk pattern or dot pattern , other pattern the effect is very light
4. H/V-Position adjustment
Set the Chroma to 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. LANGUAGE function
There are 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 C2 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.
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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
Pixel freq. = 25.175MHz (from VESA spec)
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