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Oct 28th, 2009 at 1:53pm
Regarding receive signal quality at a remote site (SQF)
If the value has been around 92 for a long time and now is around 82 then something has changed, e.g. lower transmit power from the teleport, rain fade at teleport or remote site, cross pol carrier started interfering, and quite likely: remote site dish has become mispointed or LNB cable corroded.
It is important to point dishes accurately to the maximum SQF value, whatever that value may be. Different networks (e.g. Iraq and USA) will have different peak values as will different sites in the same network, according to location in the downlink beam pattern. Just to get the value above some idea of a good enough signal (e.g. 75 or more) is not acceptable. The reason is that you must get the receive beam accurately centered (peaked SQF) so that the narrower transmit beam is centered also. When the satellite downlink power is very high is quite possible to have good quality downlink but still be mispointed so far off that the remote site uplink is struggling. This being indicated by it having to drop down from say 4/5 to 2/3 to 1/2 rate code. This should normally happen only during heavy rain to keep the service working.
When I saw the first posting above (Receive SQF reduced from 92 to 83 and transmit Rate Code down to 1/2, my thoughts were the same as Greg: Dish mispointed causing both receive and transmit to deteriorate simultaneously. Water inside the feed horn or obstruction can cause simultaneous deterioration in both directions.
sooby25rs Can you tell us what was done to restore your SQF back up from 83 to 92 ?
Best regards, Eric.
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