Skew equalization

Skew exists between wire pairs when the physical length of one wire pair is different from another. Skew affects the displayed image when the differential length between wire pairs exceeds 2 feet. This causes the timing of the red, green, and blue video signals to appear out of alignment (horizontal registration errors). The signals transmitted on the shortest pair are shifted to the left if you are viewing white lines on a black background. A white vertical line on a black field can appear as individual red, green, and blue lines that are close together. The signal transmitted on the shortest wire pair leads the other colors and appears to the left on the display. As the transmission cable length increases, the skew effect increases.

The MTPX Plus has a skew equalizer function that is available using SIS, the Matrix Switchers Control Program, or built-in HTML page control. The skew function provides separate time delay circuits on the red, green, and blue video lines on the inputs and the outputs. Each time delay circuit can be independently adjusted, from 0 to 62 nanoseconds, to properly align the red, green, and blue video signals on the displayed image. When correctly set, the red, green, or blue video signal on the shortest wire pair is delayed to properly converge the displayed video image.

UTP cable test equipment measures and reports wire pair length. The report on the various pair lengths can be used to properly equalize pair skew. If UTP cable test measurement cannot be done, pair skew can still be equalized by viewing a test pattern with a critical eye. Examine the test pattern for loss of horizontal registration and, through a process of trial and error, equalize any pair skew.

Features

Twisted pair inputs and outputs — The switchers input and output TP signals on female RJ-45 connectors.

NOTE: For low resolution MTPs (S-video and composite video) on the TP inputs, the

MTPX Plus audio circuits are compatible only with the newer generation,

mono audio models. See your MTP transmitter/ receiver and refer to the associated manual to determine which MTP models you have.

Local video inputs and outputs — The switchers directly input and output RGBHV or RGBS (VGA) video on 15-pin HD connectors. They can also input and output RGsB, RsGsBs, component/HDTV, S-video, or composite video.

Local audio inputs — The switchers directly input balanced or unbalanced stereo audio on 3.5 mm, 5-pole captive screw terminals.

Audio input gain/attenuation — The volume of each audio input can be adjusted so there are no noticeable volume differences between sources. You can set the input level of audio gain or attenuation (-18 dB to +24 dB) via the front panel or via serial port control.

Audio output volume — The volume of each audio signal that is output on the 5-pole,

3.5mm captive screw input connectors can be displayed and adjusted through a range of full output to complete silence. Adjustments can be made from the front panel or remote control.

MTPX Plus Series • Introduction

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Extron electronic 68-1383-01 REV. E manual Features, Skew equalization