Pete:
I just completed the installation of an old Primestar dish on an SG2100 motor and it works great.
1. I removed the existing mount from the dish.
2. Then I cut off the flange on each side just an eighth inch or so past the bend so it would be more rigid.
3. I bolted the flanges on the top and bottom using the same mounting holes. Now they ran horizontal instead of vertical, and the curved edges faced each other and were turned in toward the dish.
4. I knew that it was important to mount the dish as "square" as possible to the motor arm so that it would track properly. I solved this problem by removing the wall mounting bracket from an old DirecTv installation. I centered it on the flanges and drilled holes through the flanges using the holes in the wall bracket as a guide.
5. The pivot hole in the wall bracket was only one-quarter inch but the holes in the upper part of the motor arm was five-sixteenths, so I drilled out the pivot holes to match. This was necessary to keep the dish from flopping over to one side when going to a far-west position.
6. I soon found out that I needed a jackscrew in order to make fine tuning adjustments to the dish elevation. I used a one-and-a-half inch pipe clamp (looks like a question mark without the dot underneath), fairly rigid, and marked the motor arm where it needed to be mounted. I used a three-eighths inch bolt as a jackscrew and ran it through the hole in the pipe clamp. I placed a jam nut on each side of the clamp.
7. I had to remove the dish and the motor arm and use a drill press to drill a five-sixteenths inch hole through both the pipe clamp and the motor arm. I then used a bolt about two inches long to mount the clamp.
8. That completed the retrofit and it worked great. The booklet that came with the motor has a chart on page seven that lists the declination angles and the resulting dish elevation for each degree of latitude. Mine was 28 degrees, but the wall bracket that I used had no scale on it. I used my angle finder on the front of the dish in that flat area right in the center. By subtracting 28 from ninety I knew when I had the approximate dish elevation when it was pointed due south.
9. Then it was just a matter of zeroing in the adjustments. I had a little trouble there too. My pole was a galvanized 2 inch pipe that had been painted over. When I loosened the U-bolts to the point that I could rotate the motor easily without jerking and overshooting, it tended to walk down the pole. I cut the coupling portion off a 2 inch PVC pipe, split it lengthwise, and placed the halves against the bottom of the motor. I used a hose clamp to secure them. I still could not loosen the motor as much as I wanted because it would start to tilt forward. So I had to snug it up. I placed a piece of tape on the pipe and made a pencil mark on the tape and another on the U-bolt cleat. Then I could see how much I had turned it. Soon, I located my true south satellite.
10. It tracks all satellites great.
Old John
I am sure your posts and pictures will help many members.
