Tracking the arc

[LoTech]

OK, I just installed a nice plumb metal pole for the first time. Before that I had my dish and SG2100 motor mounted on a shaky landscape timber.

I installed the motor according to the manual for 37 N latitude at 52 degrees. The dish declination I set at 30 - 5.897 = 24.103. I entered my correct longitude and latitude into the receiver, set to USALS, and bam... RTV at 99%.

Now here's my problem. The farther out I get on the arc, USALS passes the correct location and I have to move the dish back with DiSEqC. For example, the motor passes 125W, and I have to move it back about 2 degrees to get signal. I have forgotten since I first set up my motor how to adjust the elevation/declination to fix the problem. Do I increase the elevation and decrease the declination or decrease the elevation and increase the declination?

 

[McGuyver]

OK, I just installed a nice plumb metal pole for the first time. Before that I had my dish and SG2100 motor mounted on a shaky landscape timber.

I installed the motor according to the manual for 37 N latitude at 52 degrees. The dish declination I set at 30 - 5.897 = 24.103. I entered my correct longitude and latitude into the receiver, set to USALS, and bam... RTV at 99%.

Now here's my problem. The farther out I get on the arc, USALS passes the correct location and I have to move the dish back with DiSEqC. For example, the motor passes 125W, and I have to move it back about 2 degrees to get signal. I have forgotten since I first set up my motor how to adjust the elevation/declination to fix the problem. Do I increase the elevation and decrease the declination or decrease the elevation and increase the declination?

It may depend on a few discrepancies. You'll have to manually find the 125W and tug slighlty on the top and bottom of the dish to see if the signal increases or decreases, this will tell you if you need to lower or raise elevation. The chart I attached should help you. You'll need to check the same way on the East side using another sat like the 74W or as low as you can, then you compare the two extremes, east vs west. hope this helps you

 

[LoTech]

Thanks McGuyver. From the picture I think I've got too little declination. I'll adjust that tomorrow and try it again.

 

[AcWxRadar]

It may depend on a few discrepancies. You'll have to manually find the 125W and tug slighlty on the top and bottom of the dish to see if the signal increases or decreases, this will tell you if you need to lower or raise elevation. The chart I attached should help you. You'll need to check the same way on the East side using another sat like the 74W or as low as you can, then you compare the two extremes, east vs west. hope this helps you

Excellent job McGuyver! :up

RADAR

 

[mikelib]

It may depend on a few discrepancies. You'll have to manually find the 125W and tug slighlty on the top and bottom of the dish to see if the signal increases or decreases, this will tell you if you need to lower or raise elevation. The chart I attached should help you. You'll need to check the same way on the East side using another sat like the 74W or as low as you can, then you compare the two extremes, east vs west. hope this helps you

Mc,
Did the picture come off of a web site and if it did do you have a url?
Thanks
Mike Lib

 

[qwert1515]

It is from: Adjusting the Polar Mount Page 3 (SUMMARY)

 

[LoTech]

Well I adjusted the declination today. The closer I got to being on the arc, the lower my signal quality got on the extreme sats. I finally gave up on trying to get USALS to pick up everything, and compromised on the declination so that USALS was on target out to about 101W, and I used DiSEqC on everything past that. That must be the sweet spot, because when I re-scanned 125W I got OETA at 99%Q on my Coolsat 8000. Not a blip on LPB though. Funny things - those S2 signals. They seem to be all or nothing on my dish/receiver. When I tried to use DiSEqC to fine tune 125W I noticed that OETA would drop from 99 to zero with one nudge to the dish.

 

[Lak7]

Not a blip on LPB though. Funny things - those S2 signals.

As of Mid February or so, I can no longer lock the LBPS TP with either my 36" Prime Focus, or 80cm Bob Jones Dishes. I must use my 10' BUD, and that is right on the edge of a clean Pic.

 

[mikelib]

It is from: Adjusting the Polar Mount Page 3 (SUMMARY)

qwert1515
Thanks, I read this web site some time ago and I remembered the picture, I forgot to put the website in my favorites. It in there now, thanks again.
Mike Lib

 

[McGuyver]

Well I adjusted the declination today. The closer I got to being on the arc, the lower my signal quality got on the extreme sats. I finally gave up on trying to get USALS to pick up everything, and compromised on the declination so that USALS was on target out to about 101W, and I used DiSEqC on everything past that. That must be the sweet spot, because when I re-scanned 125W I got OETA at 99%Q on my Coolsat 8000. Not a blip on LPB though. Funny things - those S2 signals. They seem to be all or nothing on my dish/receiver. When I tried to use DiSEqC to fine tune 125W I noticed that OETA would drop from 99 to zero with one nudge to the dish.

LoTech, don't give up yet... sounds like you got the declination set better or right on and if you see a signal drop on the extreme ends it may be an east/west adjustment you need to make. Again, drive the motor to the east and flex the dish (top and bottom) and see which way the signal increases or decreases then check the west, if you see the oposite results then you simply adjust to the east or west accordingly. Look at the chart again and concentrate only on the east/west adjustment and see what happens.

Example, If you have to raise the dish elevation on the east and lower on the west, then you slighly move the motor and dish together to the east. opposite results go west.

Don't try multiple adjustments at one time because it will confuse you.

 

[Larobpra]

My sg2100 was the same way with USALS (going beyond where it was supposed to stop - did a bench test to confirm it) so I just gave up and use DiSeqC. There was much discussion about the problem some time back.