User guide

Troubleshooting
MultiView™ II DVI-Tx Installation and User Guide 16
Chapter 6 Troubleshooting
In most cases, nearly every issue with the MultiView™ video system can be resolved by checking the twisted-
pair cable termination and making sure that it’s pinned to the TIA/EIA 568B wiring specification. However, there
may be other problems that cause the system to not perform as it’s designed. The following table lists the most
common installation errors and their solutions.
Table 3: Troubleshooting Problems and Solutions
Problem
Solution
No video signal at
the receiver
 Check that the transmitter is a MultiView-II DVI-Tx type, with the proper option
configured (-A, -S, SPDIF-mode, or –SAP) to match the receiver.
 Check that both units are powered and all necessary cables are firmly connected.
 Ensure receiver EQ and SKEW adjustments are set correctly. Use the Auto-
adjust mode (push up + down buttons simultaneously). If a manual adjustment is
necessary, change EQ settings slowly to avoid losing the picture completely.
 During initial installation of a MVII-DVI-Rx-1K receiver, it is best to start by using
Auto-Adjust mode. Once you have a video image, it’s much easier to fine-tune
the EQ setting to get the best possible image on your display.
 Make sure the twisted-pair cable is terminated correctly per the TIA/EIA 568B
wiring specification.
 Check that the display device is powered on and functioning.
 Check to ensure your chosen display is compatible with the format of the input
signal at the transmitter.
Poor video quality at
receiver
 Ensure receiver EQ and SKEW adjustments are set correctly. Change EQ
settings slowly while making manual adjustments.
 Check all cable connections.
 There may be a video-skew delay issue – your cable may have more than
65nSec of skew at its current length. If possible, use a shorter cable (or cut off
some excess “service-loop”).
 Check the twisted-pair pinout and also the connectors on the transmitter and
receiver for any bent pins or foreign objects wedged between contact pins.
Poor audio quality
 The audio output at the receiver is line-level only. An amplifier, or powered
speakers, are required. Make sure amplifier or speaker power is ON.
 Check input source levels from the source device. Ensure the audio source level
does not exceed the audio-input ratings for the transmitter (DVI-Tx). Clipping or
distortion can result.
 Audio is summed left and right for “-A” mode. If using a single channel, both audio
inputs must be connected at the transmitter end to obtain proper audio gain
through the link (approximately 1:1, input to output).
Serial
communication
doesn’t work
correctly
 Are the serial devices connected properly? Are the serial parameters correct for
source/destination devices?
 Are the serial cables terminated correctly? Is a null-modem cable required at the
TX or RX end?
 When using serial-capable receivers with video switches, distribution amps, or
multi-output transmitters, the serial data is sent transmit-only. Please take this
into account when trying to control displays or other devices. For assistance,
contact Technical Support.
 SAP units have a factory default baud rate of 9600 bps and use 3 wire (TX, RX,
GND) signals only. If necessary, use SAP-II serial commands to change the baud
rate to match your connected device.