0 Signal

[bill190]

In general the setting on the positioner for your location should be in the ball park of what it should be. If you are way off from this, then your "arc" will be off.

The bottom line is the elevation of the dish for each satellite (see below). Then the arc is adjusted with the positioner elevation "hand in hand" with the dish elevation adjustment. To change the arc, adjust one setting down and the other up, or the other way around. I make these adjustments when on a south pointing satellite. Then move dish back and forth the check the arc after adjusting.

Now different dishes have different "offsets" (value to plug into the below calculator). I have never seen this value included with the instructions included with any dish I have purchased. I have had to go to the manufacturer's web site and find the specifications for the dish! The offset amount of the dish can be 15 degrees, 18 degrees, 22 degrees, etc. and of course 0 for a prime focus dish.

For accurate aiming, you can use an "inclinometer" on the back of the dish along with a dish pointing calculator. And a handheld GPS (set to real heading, not magnetic) for direction the dish is pointing.

Here is a dish pointing calculator...
http://www.satellite-calculations.com/Satellite/lookangles.htm

 

[bill190]

At the bottom of the following web page is a diagram of the arc and how you can be off slightly with dish adjustments.

http://www.geo-orbit.org/sizepgs/tuningp4.html

To adjust the arc, while pointing at a south satellite and using the coax signal meter, move the motor slightly up and dish slightly down. Or move the motor down and dish up.

When you are done with your arc adjustment (still on south satellite), adjust the signal meter so it is middle range (5 on my meter), then press lightly on the dish with your hand to move it up - signal meter should go down. Press lightly on the dish with your hand to move it down - signal meter should go down.

If the signal goes down if the dish is moved up or down, then this means you are aiming at the satellite dead center and have a perfect adjustment for that south pointing satellite.

Now the trick is to keep adjusting the arc - moving dish back and forth, untill all satellites in the arc are dead on like this.

This took me a week to get right the first time I tried. Takes lots of patience.

Hints...

If the dish needs to go up more for east satellites and down more for west satellites (or other way around), then need to rotate positioner on pole.

If both east and west need to go down more or both need to go up more, then it is an arc adjustment.

If you need to adjust the arc up in the east and west, then you adjust the positioner DOWN and the dish up.

If you need to adjust the arc down in the east and west, then you adjust the positioner UP and the dish down.