Setup guide

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. CHAPTER 4: Troubleshooting
Problem: Serial communication doesn’t work correctly.
Solution: • Are the serial devices connected properly? Are the serial
parameters correct for source/destination devices?
• Are the serial cables terminated correctly? If a null-modem
cable is used, it must be placed at the receiver end.
• When using RS-232 transmitters or receivers in daisy chains,
Cat5 switches, Cat5 distribution amps, or Multi-output
transmitters, the serial signal is a unidirectionally broadcast
mode only. In this mode, all other MultiView™ CAT5 Video
System devices must be the simplex serial type.
For assistance, contact Technical Support.
• The last device in a T4 transmitter or daisy chain configuration
must be a receiver unit with a terminated serial board.
See Appendix E for Serial board settings.
• SA/SAP units have a fixed baud rate of 9600 bps and use 3 wire
(TX,RX,GND) signals only.
Problem: “Green shift” or “green washout” on multimedia signals.
Solution: The standard video/serial model is designed to function with DC
coupled signals in which the black level is referenced to 0 volts.
Nearly all VGA cards function this way.
Some media servers, however, provide AC coupled signals and
can cause a green color shift in the video. This is a result of the
sync clamping on the red and blue channels of the video/serial
model.
For five-component (RGB/H&V) AC coupled video, the
MultiView™ CAT5 Video System XRTx Universal transmitter
has been designed with full DC restoration capability. This
problem is easily solved via a simple switch setting in the XRTx
Transmitter. Please refer to Appendix C.
Problem: Notes on Daisy Chaining
Solution: When utilizing a receiver’s RJ45 daisy chain port, the following
rules apply:
• If using L/R summed audio, simplex serial, or SPDIF units a
maximum of 12 units may be daisy changed within the rated
cable length of the receiver.
• When using SA units, a maximum of 4 units may be daisy
chained within the rated cable length of the receiver.
• When using SAP units, a maximum of 12 units may be daisy
chained within the rated cable length of the receiver if using
standard cat5/6 or a maximum of 8 units may be daisy chained
within the rated cable length of the receiver if using skew-free
cable.
• When daisy chaining, the maximum cable distance is not
increased beyond the rated distance of the receiver used. For
example, an AK600 can only daisy chain within 600 ft of the
transmitter. It is possible to daisy chain out of a short range
receiver into a longer range receiver to increase the range. For
example, over 600 ft an AK600 can be daisy chained into an
AK1200 which allows for daisy chaining to 1,200 ft.
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