Satellite Internet forum
Service Providers >> Satellite Connection in Africa >> Need Help satellite dish pointing Angola

Message started by NoFX on Jun 4th, 2007 at 11:33am

Title: Need Help satellite dish pointing Angola
Post by NoFX on Jun 4th, 2007 at 11:33am
We mount one vsat system in Angola with an antenna of 1.2m, 1 modem linksat, 1 LNB SMW DRO 11.3. I already have the equipment mounted, the problem i  have is to point the entenna with the spectrum analyser to the eutelsat 3W, the signal this always 25%, pointed the respective cordinates. ???!!

If i  turn the antenna for north or south the signal  it's exacts the same =25%

I don't have more ideas... can any one help me plz

Lobito -  Angola
Lat:-12.36(-12°21') | Long:13.55(13°33')

Azimute: 331.66N
Elevation: 73.62
Rotation: -27.63


Title: Re: Need Help satellite dish pointing Angola
Post by Eric Johnston on Jun 4th, 2007 at 1:17pm
Your service provider should have told you what polarisation to use for the downlink.  Vertical or Horizontal. (I am assuming you are operating in Ku band, with linear polarisation)

Set up the feed polarisation rotation as follows:
1. Set to nominal.  If Vertical rotate the feed/LNB/BUC so that the broad faces of the rectangular LNB waveguide are on top and underneath.
2. Adjust 27.6 deg anticlockwise, while facing the satellite.

Your elevation angle of 73.6 deg is correct.  Use the scale on the bracket behind the dish.  Now swing the dish boldly sideways in a generally North North West direction (around 343 deg magnetic compass) and the linkstar RX LED should start flashing green as you pass the satellite.  

Your service provider should have told you a line of configuration text to type into the linkstar to set up the receive frequency etc.   This must be exactly correct.  Check every character. Use command pconf to check the configuration details have gone in correctly.

If the LNB shows no change in output regardless of antenna pointing check that the DC power to the LNB actually exists.  Do this very carefully so you don't accidentally short circuit the LNB supply.  If you are using a spectrum analyser that is not tolerant of DC applied to its input, use a DC block or isolating splitter and check that there is no DC voltage present.   Check that the centre pins of the cable F connector plugs are long enough (i.e. stick out far enough) to make contact with the spring contacts inside the F sockets at the LNB and modem.

Best regards, Eric.

Title: Re: Need Help satellite dish pointing Angola
Post by quitro on Jun 4th, 2007 at 9:15pm
Iam in Huambo, just 360 km from lobito. and I have instaled here an kuito about 18 linkstar sites.
tell me wich dish brand are you using.
wich conf. comands did you inserted in your linkstar IDU?
mail me if you need more help. I speak portuguese!
bestr regards

Title: Re: Need Help satellite dish pointing Angola
Post by NoFX on Jun 5th, 2007 at 9:17am
Thanks Eric Johnston and quitro for your help ...

I used one Channel Master antenna 1.2m

The commands inserted in linkstar IDU, i will tell you later, because i dont have here the IDU....
I speek Portuguese too ;)
David i will send you a email later to talk with you

Thanks one more time :)

Powered by YaBB 2.5.2!
YaBB Forum Software © 2000-. All Rights Reserved.