Kramer Electronics 704 - Manual (Page 28)

KRAMER ELECTRONICS LTD.
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13.2 Video Signal
Problem Remedy
No video at the output
device
1. Confirm that your sources and output devices are powered on and connected properly.
2. Confirm that all devices in the signal path have the proper input and/or output selected.
3. Try to invert polarity, using the polarity switch (TP-12N, 704, 708 Only).
4. Use a Video Tester to examine the video path leading to/from your Twisted Pair
Interface /Kramer Tool (see section 3.2 " Video Tester")
Video level is too high or
too dim.
1. The Twisted Pair Interfaces/Kramer Tools in this manual (except for the TP-1xl TP-6,
TP-11N, 705, 707, 709, 711, 712) offer termination switches on each input. Verify
that the twisted line is well matched, otherwise it results in a video level that is too
high or too dim when looping is performed and the termination switches are not in
proper position (see section 11.2 for more details).
2. Confirm that the input and output connecting cables are of high quality, properly built
and terminated with 75 ohms.
3. Check level controls located on your source input device, output display, or recorder.
Signal quality degradation:
color is fading or smeared,
quality of the picture is
reduced, details of the
picture are lost.
Inappropriate cables usually have excessive built-in capacitance. When long shielded
cables are used the capacitance grows, and the cable collects more interference from RF
sources, such as transmitters, computers and other appliances creating RF fields. At the
same time the cable also impedes the streaming of high frequency signals. As a result of
this interference, and of the high frequency loss, signal quality degrades.
To solve the problem perform the following:
1. Use high quality, non- shielded cables (UTP type) for the longer distances (Multi
Twisted Cable Wire is recommended).
2. Use a line amplifier from the TP series (such as the TP-6) to pre-compensate for
signal degradation. You may cascade several line amplifiers to extend the range.
Connect the line amplifier as close as possible to the video source.