Adder Technology AV Series manual Skew compensation adjustments AV101 & AV200 only

SKEW GB dial SKEW RG dial

PSHAR

KABGWSKE GRWSKE TBRIGH

Skew compensation adjustments (AV101 & AV200 only)

The twisted pair cabling used to link the AdderLink AV modules consists of four pairs of wires per cable. Three of these pairs are used to convey the red, green and blue video signals. Due to slight differences in twist rate between the wire pairs, the red, green and blue video signals may not arrive at precisely the same time. This effect is visible as separate colour shadows on high contrast images and is particularly apparent when using higher screen resolutions over long distances and also when using certain types of category 5e cables.

1 2 3 4 5 6 7 8

8	8	Data signal
7	7
6	6	Red
3	3	video signal
5	5	Green
4	4	video signal
2	2	Blue
1	1	video signal

To create a skew test pattern

1Run any image creation/editing application, such as the Paint program supplied with Windows.

2Using the image application create three stacked horizontal rectangles (one red, one green and one blue) that fill the width of the screen.

3Draw a vertical black line down across the coloured bars and then repeat this vertical line at intervals along the width of the coloured bars. These lines create breaks across the colours and give you more opportunities to view the horizontal position of each colour relative to the others.

To display the supplied skew test pattern

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Skew compensation adjustments are made using two rotary dials, the first affects the relationship between the green and blue colour signals (SKEW GB) while the second (SKEW RG)

operates similarly on the red and

green signals. Each dial delays one of its stated colours in relation to the other. By using both dials

it is possible to correctly align all three colours. The effects of skew

are easiest to view and adjust when distinct red, green and blue elements, in close proximity, are present within the screen image. An appropriate test pattern is supplied on the AdderLink AV CD-ROM or

alternatively you can create your own test pattern as discussed opposite.

NOTE: Skew adjustment is available on the AV101 receiver at any time. However, the AV200 must be placed into skew adjustment mode as power is applied. Please refer to the section To place the AV200 receiver into skew compensation mode.

NOTE: Both video outputs are equally affected by your skew adjustments.

1Insert the supplied Adder 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 SkewTest entry to display the standard test pattern. If necessary, select the Full screen option from the File menu to 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.

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