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Nov 20th, 2007 at 10:17am
Check your assembly: The 505 on the feed throat and the single tick mark on the rear flange of the tapered spacer should be directly and exactly away from the feed support boom. For nominal horizontal receive polarisation, the filter and LNB should also be directly and exactly away from the feed support boom.
To set the polarisation angle, the entire antenna should be rotated clockwise by approx +45 deg (for Iraq and W3A), while facing towards the satellite. Set your polarisation angle exactly to the calculated value plus 3.5 deg using the large scale at the rear. If the hub has not asked you to do ACP testing don't.
Your antenna should look like this (for Iraq and W3A):

Pointing. The signal power now from the W3A satellite is exceptionally high so it is easy to find the satellite, but just any very high reading does not mean it is good enough.
For example: If you get a reading of 90 and the maximum possible is 97, then the 90 represents bad and unacceptable pointing. The receive side may work fine but the transmit won't. You need to get to the exact receive beam centre so that the narrower transmit beam is pointed properly.
In azimuth I suggest loosening both nuts 1 turn (i.e. 6 flats) and then gently pulling and pushing the dish to rest against each nut alternately. Adjust the nuts till you get exactly the same degraded signal on each side (e.g. 51) The exact number does not matter, what does is that both numbers should identical. Then wind in both nuts by the same number of flats so that you are in the exact centre.
In elevation, mark one flat on the lower nut with felt tip pen. Wind the lower nut in 1/2 turn increments and record the quality at each position, then adjust back to the peak.
None of the above may help with your particular problem, but the above is for other readers also.
Check your transmit cable is connected to the IFL (inter facility link) socket on the transmit module. The adjacent socket, marked API, is not used and should have a cover over it.
Check your location coordinates again in the configuration page. Check all the other details also. Send me a copy of the configuration document to eric@satsig.net and I will look at it to see if I can spot any typos that might explain the problem.
It is not a good idea to connect up the transmit cable until you have a perfect receive signal and dish pointing is finished. Then power off at the AC mains wall switch (never disconnect the low volatege DC cable between the power supply module and the modem). Then connect up the transmit coax cable. Then phone the hub and power on when told. Do not touch or interfere with the antenna or modem during commissioning, while new software is being downloaded and configured.
Best regards, Eric.
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