Black Box ACU5114A, ACU5116A manual Skew adjustment, To use skew adjustment

Convergence test pattern showing the RGB crosses. In this case, the green signal can be seen out of line with the other two colours.

Skew adjustment

The twisted pair cabling supported by the Wizard extender modules (category 5, or higher) consists of four pairs of cables. Three of these pairs are used by the

modules to convey red, green and blue video		1 2 3 4 5 6 7 8
signals to the remote video monitor. Due to the
slight difference in twist rate between these
three pairs, the red, green and blue video signals
may not arrive at precisely the same time. This
is visible as separate colour shadows on high
contrast screen images. This effect is particularly	8	8	Data signal
apparent when using higher screen resolutions	7	7
	6	6	Red
and some types of category 5e cables.
	3	3	video signal
In this situation, the Wizard extender modules	5	5	Green
	4	4	video signal
provide internal skew adjustment that can help	2	2	Blue
to rectify the situation. The skew adjustment	1	1	video signal

works by delaying or advancing the timing of any of the red, green or blue colour signals so that they are all delivered to the monitor at precisely the same time. For best results a test pattern is provided and this should be displayed when using skew adjustment.

To use skew adjustment

1 Insert the supplied Installation CD-ROM into the CD player of the computer.

2Within Windows, use the My Computer option (usually available as a desktop icon or within the Start menu) to view the contents of the CD-ROM. Double-click the Skew entry to display the standard test pattern. If necessary maximise the application window so that the image fills the screen.

The screen will show a series of fine red, green and blue crosses which should all be in line, vertically and

horizontally. Skew affects the horizontal placement of the colours and using this pattern it is much easier to discover which, if any, colours are being adversely affected by the twisted pair cable run.

3 Simultaneously, press the hotkeys (by default, and ) along with to enter configuration mode.

The three keyboard indicators (‘Num Lock’, ‘Caps Lock’ and ‘Scroll Lock’) will now begin to flash in sequence.

®

4	As appropriate, press either the R, G or B keyboard keys to select the
	appropriate colour channel. Corresponding keyboard indicators
	will flash rapidly to show which channel is currently selected					l
						k
						Scrol
	for adjustment: Num Lock for Red, Caps Lock for					Loc
					k
					Caps
	Green and Scroll Lock for Blue.				Loc
				k
				Num
				Loc			
						l
						k
						Scrol
						Loc
					k
					Caps
					Loc
				k
				Num
				Loc
						l
						k
						Scrol
						Loc
					k
					Caps
					Loc		
				k
				Num
				Loc
5	Press the	and	keys to retard or advance the timing of the selected
	colour channel respectively. On screen you will see a change in the position
	of the selected colour crosses in relation to the other two.
		Restore					  
		default
		skew
		settings
	Exit image
	controls				Advance
	and save				colour		 
	settings				timing
			Retard
			colour
			timing
6	When the selected colour crosses are correctly positioned, press					to	 
	exit that colour channel. The keyboard indicators will return to flashing in
	sequence.
7	If required, repeat steps 4 to 6 to select and adjust any colour channel until
	the vertical lines of the red, green and blue crosses are all aligned.
8	When all colours are correctly aligned, press			to exit configuration mode
	and permanently save all settings.

Note: Once you have made a skew adjustment, it may be necessary to re-	18
adjust the image controls to attain an optimum screen image.