SatSig topic:

HN7000S best signal is 29

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Jun 29^th, 2008 at 8:14pm

i have a hn7000s my dish is pointed at 227 azimuth, polarisation +40 and elevation at 37.

I'm at 44 east 33 north my feed horn is set up with 505 number and the single hash mark on the throat is away from the assymbly like i've read here on site.

In my info i got with the dish my lnb polarization is vertical and tx polarization is horizontal in the manual commissioning info were u enter al the info for your modem i have it as recieving polarization vertical and transmit polarization horizontal is the receiving and and transmit backwards??

I've tried switching them but it only worsens and i know everything else is correct in my info weve tried sweeping the sky and everything but best signal is 29 donno if you can help.

Jun 29^th, 2008 at 9:10pm

If your nominal receive polarisation is vertical then the LNB filter arm should be attached to the spacer tube so that the LNB filter arm is sticking out sideways. The system will now be receiving vertical polarisation. This is the starting position. The single tick mark on the spacer tube must be directly away from the support arm. The Prodelin documentation in the antenna box can be misleading as my copy refers to polarisation setting but neglects to say that this refers to the transmit polarisation.

Now apply the +40 polarisation adjustment angle by turning the entire dish using the large circular polarisation scale on the back. +40 deg positive means clockwise, while facing towards the satellite.

Your polarisation is set manually by you. What is says on the screen is just text. If it does not match reality then the hub has written the text wrong in their hub config.

Best regards, Eric.

Jun 30^th, 2008 at 9:54am

so just move the whole thing so that the single mark and the feed numbers are still directly away but it now on the side ?? kk ill try it ty

Jun 30^th, 2008 at 10:07am

i dont spose u could post a picture with what you mean ive tried posting one but these computers im on dont let me pull pictures i tried rotating it but just turning it gives it a 80 polarity is that how u ment to rotate it or the whole thing so that it staying at 0 according to the nnumbers on the brakets?

Jun 30^th, 2008 at 9:04pm

The single tick mark on the spacer tube must always be directly away from the feed support arm.

There is a joint, with 6 small screws, where the filter/LNB assembly attaches. There are two alternative positions.

If the filter arm and LNB are at the side, either side, the nominal receive polarisation is vertical.

The image above shows vertical nominal receive polarisation.

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If the filter arm and LNB are at the top, away from the feed arm, the nominal receive polarisation is horizontal.

The image above shows horizontal nominal receive polarisation.

The two small white yokes may now be finally tightened, exactly in the middle or exactly sideways.

Polarisation adjustment: If you have the Prodelin dish with the mode match feed there will be a giant circular polarisation scale behind the dish where you set the polarisation adjustment angle. You rotate the entire reflector and feed arm and radio assembly as a whole using this giant scale.

The image above shows the polarisation set to +30 deg. The whole dish has been turned clockwise, while facing towards the satellite. During this polarisation rotation, the beam pointing remains fixed, unchanged, towards the satellite, and at right angles to the metal polarisation plate scale where you can put an inclinometer. You need to set about +43 deg (my guess).

If there is confusion about whether or not you are supposed to be receiving nominal horizonal or nominal vertical, don't worry. Just set is one way correctly, with the single tick mark exactly away from the feed arm. Then you can turn the dish +40 deg clockwise; if no good, turn a further 90 deg to +130 deg. That will enable the opposite polarisation. It will work perfecty well, even if it looks unusual with the feed arm high up. Note the beam will stay pointed at the satellite all the time.

Best regards, Eric.