iDirect AM22 pointing need help!

Hello all,

    I have also posted this in the iDirect forum. I need some help in pointing a dish in Iraq to AM22. My 3000 series has the options file loaded and using iSite software dish pointing I can only get 2.5 volts while pointing. Using a Horizon sat meter for Afg 11.3 Ghz I also can not get a lock and the strongest signal I can get is 69 dB. 

    I have a andrews 1.2m dish and confirmed with bently walker that I have the correct BUC and LNB. They even sent me a picture of a working iDirect in Iraq and my dish setup looks exactly like it. I have double checked the elevation, azimuth and polarity ten times but still connect get a strong signal.  I have pointed antennas and set up systems to W6 and W3A etc so I am not a newbie when it comes to this. Can anyone provide any insight as to what might be the problem?

Hello,

    The W3A pointing was for an HX system which is up and running. My other system is a 3000 series on an andrews 1.2 trying to get on AM22. I will try and find a multimeter but I gues my question would be; why wouldn't my LNB be getting the proper voltage? Is that a setting set by the options file?

I as of yet don't have a multimeter but I have tested the cable with the sat meter and the following are my results. Hooking my Horizon HDM V2.5 meter directly to the LNB with a ten foot cable, in a twenty degree elevation and azimuth scan of the sky with the AM22 Afg 11.3ghz meter file, I can only find two satellites.

Using the short cable, I can get one up to 65 dB and one up to 68 dB. I tested with the stronger signal. Hooking up two different 30 meter cables provided by Bently Walker, both cables drop the dB down to 63 dB inside at the modem from 68 dB. I imagine that is just because of the resistance in the longer cable.

Both cables are testing exactly the same. I think the chances of both cables being bad and providing the same results are pretty slim. Tesing outdoors with the shorter cable, if I twist the polarization away from the optimal setting of -13, the dB reading does drop.

Using the iSite software and antenna pointing, the sky is also completely clear and shows .3 volts (nothing) besides the same two satellites. On the satellite that I get a 68 dB reading, I can only peak up to 2.72 volts, but it is a definite signal. I have read all of the AM22 iDirect posts I could find on here and still I do not have a clear solution to what my problem would be.

One guy had the wrong LNB. Bently Walker says I definitely have the right LNB. I have also included some pictures of my ODU. The only thing I can really think of is that my LNB is not working properly?

What is the downlink carrier frequency and polarisation you are supposed to be receiving?.

Your LNB is model NJR2754H intended for Input=12.25 to 12.75 GHz     LO=11.30 GHz    Output=950 to 1,450 MHz

Does the iDirect carrier tuning match with the calculated L band cable frequency = Sat Freq - LNB LO freq?

Does the receive polarisation make sense?  Vertical means start with the broad faces of the LNB waveguide on top and underneath.  Horizontal means start with the broad faces of the LNB waveguide on either side.  

Polarisation adjustment is then about -10 to -15 deg anticlockwise, while facing towards the satellite (for AM22 and Iraq). See Satellite dish pointing in Iraq for exact angles.

From your images you are set to nominal horizontal polarisation, adjusted correctly, approx -15 deg anticlockwise.

You refer to "Horizon sat meter for Afg 11.3".  My guess is that the Horizon has been programmed to receive some carrier using an LNB with an 11.3 GHz LO frequency.   You don't say what satellite or what polarisation.   Note there are four different beams from  AM22.  The best beam for Afghanistan does not extend as far as Iraq. See http://www.rscc.ru/en/satellite/zones/zone17.html

The Horizon meter is only good for identifying satellites if you know what polarisation and what LNB LO frequency to use.

The tech details of the LNB and BUC are here http://www.njr.co.jp/e_frame/ef_05mc_02.html

Best regards, Eric.

Eric,

    I do get the best dB out of the meter while the polarization is set at -13 deg. I have rotated the polarization full range either direction and -13 is the best for dB. In iSite, it does not say anywhere whether I am set for horizontal or verticle.

Eric,

    Ya, I turned the feed 90 deg all directions and it did not help, the signal weakened. I have pointed Bently Walker techs to this thread so hopefully I can get some more spotlight on this.

With my dish being on tall hesco dirt holding baskets, it's hard to get level pictures from the sides. The dish is set exactly at a 48.5 deg elevation. From this setting I have scanned the sky 20 deg off in both elev and azimuth. I can only find these two satellites in the swing with both the sat meter and any voltage readings in iSite. I am pretty sure one of the two is AM22 but like I said, I can't commision the modem if the LNB  is getting such little voltage for some reason.

Satbaja,

     My diss is pointing out into the open desert. All of the antennas are behind my dish. My base has about 200 satellite dish's working so hopefully there is not much interference.

I searched again for AM22 today but I could only manage 5 volts. Thisw is after Bently Walker sent me a new options file.

Bently Walker did some config settings with myself. They said they had loaded it with W6 iSite and not AM22. Once that was corrected, he also double checked the modem parameters through telnet. In theory, I should now have had no trouble finding the sat.

But to no avail, I can still not get above 5v in iSite antenna pointing. The Sat meter says it's AM22, I get the highest voltage (5v) out of that sat in iSite, it's the correct elevation, azimuth and polarity.

I am at a loss, very frustrating.

Satbaja:

rx_freq = 1237090000
rx_acqrange = 1800000

I still can only get a maximum of 5 volts, increasing the arc range did not appear to change anything.

Would anyone else have an idea why it would be this hard to get the proper voltage? Could I have bad equipment?

Update: I hired a local tech here on the camp to come over and take a look.

He had a different kind of sat meter then I have but also found AM22 in the same location I had. He tested both 30m cables with a voltmeter leading to the dish and all four leads tested good. He double checked some settings on the modem and in iSite, options file etc.

Like I, he could not get a lock with the modem. No green lights and only 5 volts in iSite antenna pointing. Needless to say, the issue is not resolved and I am out some money.

So what would you all think are my options? Could the modem iteself be bad? Bently Walker offers iDirect also on W6. I could swap out the LNB and BUC. I know for sure I can get W6, I have a DVB-S2 system running on this same dish before. But if the modem is bad, obviously switching satellites won't change a thing.

I had a similar problem in Mozambique where I knew for a fact I was spot on the sat but could not push more than 4V . I eventually changed the LNB and problem was solved .