SatSig topic:

Trouble with W6 from Iraq

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Nov 5^th, 2010 at 12:52pm

I am having trouble like many of the posters here finding the right satellite to lock on to. For my location I have received pointing instructions from the company similar to these off the website

Dish elevation= 44.6, Azimuth= 211.8 (magnetic compass), Polarisation= 29.3

The difference being that the company told me to set the polarization to 60 (90-30 right?)

from the starting position (I have the fixed feed horn assembly) my LNB is horizontal with the cable left as I'm looking at the satellite. I have the dish pointed exactly(well as exactly as you can with a paper inclinometer and compass) at that location and I am able to get a satellite with 29 signal strength. If I check other satellites in the arc (up left or down right) I am able to find multiple that give me no increase in signal strength. I have tried rotating the dish clockwise 60 for polarization and everything in between/opposite with no change in signal strength above 29. I've emailed my system status data to the tech support (off on friday/saturday) so I'm hoping you guys can help me get my signal up so when they get back to work I can get online. One email they sent me was an example setup page that different slightly from the one on my HX50 and had a frequency of 13728 while they told me to enter 13721.

Any help would be much appreciated
thanks
Zach

Nov 5^th, 2010 at 1:27pm

Regarding the polarisation setting and adjustment.

You can start with the Universal LNB (HughesNet part number PN 1501882-0002 ) with the cable connector pointed upwards, downwards or sideways.
Upwards or downwards = Vertical name polarisation
Sideways = Horizontal name polarisation.

Then apply the adjustment:
+30 means turn 30 deg clockwise, as viewed while standing behind the dish and looking forwards towards the satellite in the sky. Turn in the correct direction by the correct amount. The scale tick marks will help you count the amount. The scale numbers and any +/- should be ignored if they are wrong or go backwards from 180, 90. A result of 60 for a +30 adjustment is quite plausible - it all depends on the particular yoke scale.

When you get 29 you are on some satellite. Try the two different polarisations, which are exactly 90 deg apart. One will work (wanted signal), the other not at all (100% interference). Intermediate polarisations will not work due to clash between wanted signal and cross-pol interference.

You need 22kHz tone on/off set correctly for universal LNB PN 1501882-0002.

You also need correct tuning and symbol rate for the wanted carrier.

Best regards, Eric.

Nov 5^th, 2010 at 1:36pm

Thanks for the quick response. I have tried rotating the dish to every polarization combination I can think of. Shouldn't it change the signal strength? I can't get pictures on here right now but I will try tomorrow. as a description of my actualy setup

looking at the satellite from behind my dish with the system unrotated the LMB is facing to the left horizontaly. this is also the position where the scale on the back reads 0. If I rotate the dish from this position it would be horizontal polarization correct? so by converting the 30 to 60 (90-30) I should then rotate 60 clockwise to set 30 vertical from that start position? I still don't understand why the strength isn't changing as I rotate the dish(I may need to adjust slightly but can get it back to 29 only.
Zach

Nov 5^th, 2010 at 1:43pm

If there are equal power carriers on both polarisations (the wanted carrier on one and crosspol interfering carriers on the other) then as you rotate the dish the total power will stay constant.

The wanted signal gradually declines and then rapidly drops to none when you are exactly the wrong way by 90 deg.

The cross-pol interference is none when you are correctly set, it increases rapidly as you misadjust the polarisation and gradually increases to a maximum when you are 90 deg wrong.

When you are 45 deg wrong the wanted and cross-pol are both half power, so it wont work, but the total power is still the same. 29 is the maximum for noise power reading.

There are only two polarisation positions worth trying, both are 30 deg clockwise from starting positions with the LNB cable to the side or upwards. Don't bother with intermediate positions just flick it by 90 deg between the two alternatives.

Clockwise means as viewed with you standing behind the dish and facing forwards towards the satellite in the sky. If the scale starts at 0 it will end up at +/-30. If the scale starts with 90 itr will end up at +/-60 or +/-120, i have no idea. All you need to do is move it by an amount of 30 clockwise from a starting position.

If you want Horizontal polarisation with Universal LNB PN 1501882-0002 then start with LNB cable plug sideways.

If you want Vertical polarisation with Universal LNB PN 1501882-0002 then start with LNB cable plug upwards or downwards. Turn the entire dish 90 deg anticlockwise so the feed support arm is on the right hand side. Then bring the arm down clockwise by 30 deg.

Best regrards, Eric.

Nov 5^th, 2010 at 1:45pm

Thanks, I'll go rotate some more and post my results