User`s manual

100-M0145X2 35 of 36
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Appendix C – Troubleshooting Section
Fault Action
No RF Link
• Check if Input Source selected as RF
• Check if the following parameters of the Transmitter and
corresponding Receiver match:
-Frequency and Bandwidth
-Guard Interval
-Spectral Inversion
• Check if the down converters operate correctly:
-Correct LO is set
-BDC power is On.
Poor Link Performance
• Interference. Should an interfering RF signal occur on the
same frequency the performance of the link will be
affected. Remove the interferer or move to an alternative
frequency.
• Reduced transmit power, ensure that the attenuation
setting on the transmitter is appropriate for direct output,
or for amplifiers connected.
• No Diversity operation. Ensure both down converters are
operational.
Blue screen or Frozen screen at receiver
Check RF/Demod Lock– see “No RF Link” section above. If
Demod Lock is OK but Packet errors are not 0 then see
section Poor Link Performance above.
If the RF/Demod Lock is OK and packet errors are 0 then -
Check video is enabled at the transmitter with the
proper/matching format.
-Check correct unit name is selected at the receiver to
match the transmitter.
-Check scrambling keys are matched.
Reduced Image quality
•Image quality is affected by the selected horizontal
resolution. The image will become progressively softer for
each horizontal resolution below the sharpest resolution
of 704 pixels. It is advisable to select a horizontal
resolution that matches the resolution of the camera.
•Image quality is also affected by the video bit rate which
can be read from the video bit rate field of the transmitter
controller. The standard setting is 2.3Mb/s. However
enabling audio, particularly the high quality audio modes,
will reduce the video bit rate substantially. Therefore
ensure an appropriate audio mode is selected or audio is
fully disabled.