The tube sticking out of the motor (or the dish itself) should point due south when the motor is at zero degrees. This is regardless if there is a satellite at that position or not.
It must aim there to get the arc correct. Of course, that is difficult to judge your aim accurately, so simply try to guestimate it the best you can with a compass. You will correct any error in this aim once we start capturing satellites and fine tuning the arc.
First you need to determine your precise coordinates (latitude / longitude). Easiest method is to use Google Earth and position the mouse cursor over the spot where you will install the dish. At the bottom of the image, it will read out this information in degrees / minutes / seconds. You need to change that to pure decimal degrees. Take the minutes portion and divide by 60 and add that to the degrees portion. You don’t have to bother with the seconds portion, but if you want to, divide that portion by 3600 and add it to the degrees portion too.
Enter the pure decimal coordinates in your receiver’s USALS setup menu. Ensure that the longitude coordinate reads WEST and not EAST. You will need to enter the installation (motor setup) menu for any satellite in the list and select USALS so that you can enter the coordinates. Once these coordinates are entered for any one satellite, it is recorded for ALL satellites in the list that you select to use USALS.
Connect the motor to the LNB IN port of the receiver (the dish does not have to be attached to the motor yet and the motor does not have to be mounted on the mast yet, either). Then in the USALS setup menu there should be a "GOTO ZERO" or "GOTO REFERENCE" command. Execute that command to drive the motor to zero degrees or the center of its range of travel.
Ensure that the mast is absolutely perfectly plumb (vertical). Use a level on the east/west/north/south sides of the mast and align the mast so that the bubble is centered from all sides.
This is VERY critical so don't fudge on it.
Now you can attach the motor on the mast. Set the motor LATITUDE angle to the degrees of your site's latitude coordinate. Some motors have two different scales (LATITUDE and ELEVATION). Use the latitude scale (or subtract your site latitude from 90° and set the elevation angle to that degree). Elevation + Latitude = 90°. You can place an inclinometer on the FLAT bottom of the motor and read the ELEVATION. A dial inclinometer or a digital one will allow you to read the elevation to a higher degree of accuracy than using the stamped scale on the motor bracket.
Then attach the dish to the motor tube. Ensure that the dish clamp is perfectly centered on the motor tube. There should be a seam or two on the motor tube. Align one of the seams with some center feature of the dish bracket. Often there is a cutout or hole in the dish clamp that you can see the seam of the motor tube through, use that if present.
Determine what your dish elevation should be from the manual and set this angle on your dish. The manual may be incorrect for this motor. Use 30° where the manual states 40°.
At this point you should determine your NEAREST true south linear FTA satellite. If your longitude is, for example, 96.2W or 97.8W, use Galaxy 19 @ 97.0°W. Set this satellite up to use USALS motor positioning and then command the motor to GOTO SAT or GOTO POSITION. Some receivers state it a little differently, but they all calculate a DiSEqC 1.2 string to be sent to the motor that tells the motor which direction to move and how far.
Attach the LNBF to the dish. Set the polarity of the LNBF to zero degrees. The polarity is often called the skew, but that is an improper terminology. The polarity is the rotation of the LNBF in the LNBF clamp, CW vs CCW. Set the LNBF focal distance from the dish to the center of its range to start out with. After you find a signal, you can move it in or out in the clamp to fine adjust the reception.
Now you need to select a strong transponder signal to monitor the signal QUALITY from. Determine which satellite is nearest due south and then research what the best transponders are to use on that bird. You are NOT required to use the nearest due south satellite, but it makes the calibration process much easier and quicker. The closer you start to true south, the better.
Command the motor to move to the satellite you are going to look for first and monitor the signal quality on that one transponder that you researched. With the motor clamps on the mast just barely loose enough so that you can turn the motor on the mast by hand, position the motor to aim roughly in the direction (AZIMUTH) that dishpointer tells you where the satellite is.
Then rotate the motor CW / CCW on the mast, one direction and then back. As you rotate it, move a tiny fraction of a degree and pause for a few seconds, then move it again and pause again. Once it locks onto a signal, you will need to verify that it is the correct signal. Try running a "TRANSPONDER" scan and see what channels you log in. Check Lyngsat to verify if those channels match what is supposed to be on that transponder on that satellite.
Once you have located the proper satellite, you can fine adjust your dish elevation, motor azimuth and the LNBF polarity and focal distance to optimize your signal quality.
DO NOT adjust the motor latitude! Once that is set up initially, you never tweak it.
Now tighten the motor clamps on the mast, but not too tight, just enough so that it won't move.
Next step is to calibrate the motor and dish to the satellite arc.
Pick out two good FTA linear satellites which are as close to being equadistant (one to the east and one to the west) from your nearest true southern satellite that you just located. Try for two sats which are 10 - 15 degrees away from your nearest true south sat. Determine a really good, strong transponder on each of those.
Command the motor to drive to one of those satellites and monitor the signal quality from the hot transponder. If you are detecting a fairly good signal, grasp the dish from behind like a steering wheel and ever so gently try to push/pull the dish east or west to see if any improvement can be made to the signal. If you can improve the signal, loosen the motor clamps just enough to be able to move the motor and rotate it on the mast in that direction. Retighten the clamps.
Command the motor to drive to the other satellite in the other direction and monitor the signal quality from the hot transponder on it. If you are detecting a fairly good signal, grasp the dish again and this time, try to pull/push the dish up and down and determine if any improvement to the quality can be made. If you can improve the signal, loosen the dish elevation bracket just enough to be able to move the dish and position it in that direction. Be careful that the dish doesn't fall all the way down! Retighten the clamps.
Go back and forth between these two satellites and repeat the steps over and over until no more improvement can be made. Just remember to adjust ONLY the motor azimuth on one side of the arc and the dish elevation on the other side. It does not matter what you adjust on either side, just ensure that you stay with that selection throughout the entire calibration process and ensure that you ALWAYS monitor the SAME transponder on each satellite. This way you know that you are remaining consistent with your source signal level.
Then pick two satellites FURTHER away from your nearest true south satellite and repeat the entire process. Keep going out further and further until you have covered the entire arc.
This can be a time consuming process, so dedicate yourself the time to do it right. Be very patient and don't get greedy. When I say "GREEDY" I mean don't get impatient and start adjusting other angles and parameters to peak the signal Q on one satellite. Stay true to adjusting one thing and one thing only and the entire arc will eventually fall into place and it will be RIGHT!
You can also read my post "How to set up a motorized Ku band dish" in the FTA FAQ's section. Good luck and happy hunting!
RADAR