Dish and motor adjustments

[turbosat]

I think I know the answer to this but I want to put it before the panel of experts here, who may have done this very thing:
On my motorized dish, which was a .90 Channelmaster/primestar dish to a DG380, I decided last week to upgrade to the 1m size dish, since I had an extra one not in use.
The hole pattern in these dishes is exactly the same, so all I did was unbolt the smaller dish and put the bigger one in its place. And I did notice improvements in some of the signals, until I started looking for 125W a few days later. All I can get besides scrambled programming on that satellite is the channel that logs as SD07, usually color bars. Today I took the tv out there and hooked it all up to the old traxis 3500, ran the dish over to 125. Weak, weak. I can improve it by pushing down on the dish a little. 123W is off a little bit too. 121 seems strong.
In theory, all I should have to adjust on the dish is the elevation, correct?? With maybe some small east/west adjustments on the motor bracket. The smaller dish was doing fine from 72w to 123w and that's far as I really needed it. Now the bigger dish is fine from 72w to about 121w,then the signal strength gets weaker.
Before I mess it all up and have to start from scratch, does my theory sound logical? Or is all I really need to do is fine-tune the east/west of the motor/dish assembly. Pole is still good and plumb. It's a home-made dish bracket that's holding the dish to the motorshaft, and has been stable for over 3yrs now.

 

[skyscanner4ever]

yeah you are hitting 125 with the sd07 channel, that is a pbs. Alot of the 125 pbs channels are in hd though. the sat 123 is a good one and the signal is strong there too. You should be able to hit both sats at a high quality if tuned in right. I had the same problem once with a motorized dish and what i did was go to 125 and slightly adjust the elevation until I got my peak signal quality and then lock it down there, then go back and check the other sats and you should be locked in.

 

[FaT Air]

I'd theorize that the bigger dishes narrower beam width is uncovering tracking inaccuracies. Sounds like some fine tuning is in order. Maybe setting the Latitude angle on the motor to the "modified" angle will improve tracking out on the ends.
Think you're near 34°N. so the modified angle is 34.6°.

 

[turbosat]

I got it, mostly. You hit the nail, I think, Fatair, it was a combination of azimuth and elevation, plus I didn't really have the elevation on the dish correct, All the charts I could find said 25degrees, but then I looked at the one in the DG380 manual and it said 27degrees, dishpointer said 30....you get the idea. Just like with the c-band polar mounts, it ends up being a trade off of compromising angles (you settle with WHAT WORKS, not what the supid calculators say, lol). The azimuth was the biggest thing, once I tweaked that some, 123 popped right in, and I was tickled! I still have so dang many trees on site that it makes it tough to know if you're tracking well, or if you're hitting treetops or branches, and offset dishes make that hard to tell.

 

[FaT Air]

Well, a motor is nothing but an enclosed polar mount, so the "theory' is the same. Calculations, and the ever present measurement inaccuracies, only get you close. Getting "ON" takes a little longer.

 

[turbosat]

One thing I noticed during this little project, checking the dish elevation by placing your angle-meter directly in the center of the dish's face seems to be fairly accurate way of doing it after all.
Never was sure if I could trust that method. Couldnt get a flat surface to check it by on the back side of the dish, but the reading does equal what most of the dish-aimer sites said, around 27 degrees. Once I got the angle there, got a lot easier to correct the azimuth.