Skew delay compensation – Extron Electronics MTP SW6 User Guide User Manual

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Skew Delay Compensation

CAT 5/5e/6 TP cable can lead to registration errors between the red, green, and blue
video signals. Pair skew can be measured with test equipment or identified by viewing
a crosshatch test pattern with a critical eye to determine if either the red, green, or blue
video image leads (appears to the left of) the other two video images.

NOTE: Skew correction should not be necessary when Extron Enhanced Skew-Free A/V

UTP cable is used and the transmission distance is less than 1,000 feet (300 m).

NOTE: Unless the TP cable lengths are changed, these settings should need to be made

only once, during installation.

NOTE: For best results, repeat the skew compensation for each input.

The switcher has built-in skew compensation capabilities for its TP output. Adjust the
equalization as follows:

Select an input

Zero the skew delay for red, green, and blue as follows:

Use a Tweeker or other small screwdriver to press and hold the Delay Select
button for 3 seconds. The Delay Red, Green, and Blue LEDs all go out.

Release the Delay Select button.

Use UTP cable test equipment or examine the displayed video image with a critical eye
to determine which video signal — red, green, or blue — is most shifted to the left.

TIP:

The Extron VTG 300 or VTG 400 are recommended to provide a crosshatch
test pattern, which is ideal for determining skew. A black background with
vertical white lines can also be useful.

Adjust the leftmost video signal as follows:

NOTE: The switcher cannot shift the rightmost video image to the left.

Use a Tweeker or other small screwdriver to press and release the Delay Select
button until the LED lights for the left-shifted color — Delay Red, Green, or Blue.

Slowly rotate the Delay Adjust control clockwise while monitoring the display.
Observe that the leftmost color shifts rightward one step at a time. Continue to
rotate the control until that color is properly converged.

NOTE: A 2-nanosecond adjustment is very fine. Up to 10 nanoseconds of

delay may be necessary before you detect a change in the display.

Use a Tweeker or other small screwdriver to press the Delay Select button one
more time to save the most recent adjustment or allow the 10-second timeout to
elapse.

If one of the remaining colors is left shifted, repeat steps 3 and 4.

Repeat step 1 through 5 for each input.

MTP SW6 • Installation and Operation