Quote:
Originally Posted by pmb1010
I thought about this for a while.
I can see if you were at the equator, and the pole was tilted parallel to the equator, shifting side to side it would still track the arc.
but if it was north or south tilted, I dont see how you could compensate for that...
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Yeah, I thought pretty much along the same line. I could easily see how you could make up for tilt to your south or north, just by increasing or decreasing the motor elevation, but it wasn't obvious how to compensate for tilt say to the southwest or something. However basically, all you're trying to do is get the motor's axis to be nearly pointing toward the north star. It turns out that by a combination of changes to the motor elevation and rotating the whole mount on the pole, that you can always bring the aim of the motor's rotation axis back toward the north star. If for example, the tilt is to the southwest, the axis would be pointing a bit high and west. If you rotate the mount clockwise on the pole, it will bring the axis back to pointing north, but it will be too high or low, but if you then alter the elevation to correct that, it will be the right elevation, but not pointing north anymore. But after a few back and forth adjustments, you can hone in on the proper aim. A fellow, who's name I forget used to sell a gadget called Arc-Set or something (I have one, but I'm too lazy to go look), which is a magnetic adjustable triple level, ie 3 levels in one. With a big dish with good surfaces related to the motor axis, dish aim, and a compass for true south, you could quickly align a dish even on a tilted pole. I did it on my tree mounted dish several months ago, although it's alignment didn't last long, since the tree was still growing. But basically, just hold the one level on a surface parallel to the motor axis, and change the elevation and rotate on pole until the level indicates right while
aiming north.
On a small dish, it would be harder to do, and USALS wouldn't work unless you reset the motor's zero, but you could get it to track.