Poty orientation

  • The uplink uses circular polarisation so the line-up does not matter.


    That is not true for the receiver which is vertical for the NB transponder and horizontal for the WB transponder. For this reason, the angle of the LNB *does* matter. What makes things worse is that unless your azimuth is 180 degrees, your view to the sat will be squinted. For this reasons, for optimal performance, the LNB must be twisted a little bit. You can use sites like dishpointer.com to find the "LNB skew".
    Note: there is an easier way: it is easier to find the null of the signal and the max is 90 degrees away. So, turn the LNB to "null" the signal (for instance, beacon), then turn the LN exactly 90 degrees CW or CCW and you are set.


    The 3rd issue is the distance between the base of the POTY and the black plastic carrier of the dish. I think your POTY sticks out much too far: I think it should be flat (but someone please correct me!). You will run into two problems if you do things this way:

    1. the SMA connector is in the way. From the picture I think you have a TRIAX dish. Instead of the plastic bracket, metal brackets do exist and those just need a small bit filed away and then the SMA connector goes.
    2. The edge of the POTY base plate may interfere with the pipe that carries the LNB. LNB brackets assume a diameter of 40mm, and the POTY pipe is 22mm so you use a spacer. BAMATECH has spacers that are off-center which solves this problem

    Hope this helps!