Quote:
Originally Posted by manaman
Wejones thanks once againg, but can you please explain what you are trying to say below . I don't understand
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Not easy with drawing a picture. I may try making a graphic later if I can.
However aligning a
motorized system is a 3 step process, ie basically 3 angles to set, the declination, the motor elevation, and the north/south alignment of the motor axis. Usually you set the declination (=dish elevation on small offset dish) and/or the motor elevation while peaking on your due south satellite, then you leave this setting alone. The third angle, ie the north/south alignment is usually peaked on a satellite nearer your east or west horizon. You get close to the proper N/S alignment when
aiming your system at your due south satellite, but this generally isn't accurate enough to get proper tracking. But you can get good accuracy with this alignment when on a sat to your east or west.
However the problem, is when you run the motor to one of these sats, and try to turn the mount on the pole to do this adjustment, even though the proper adjustment takes you to the arc, some times takes you to a spot on the arc that is no closer to the sat than you were before, ie it might take you to the arc a bit east or west of the sat, so to find out if you are in fact on the arc, you need to peak by moving the motor back and forth. With these small offset dish motors, if the motor's zero is properly centered, this shouldn't happen, and the bumping process isn't necessary, but if the zero position is off, it will.
I generally look at the quality reading for a channel on an extreme satellite, then move the whole mount on the pole by a very small amount, then, using the buttons on the motor peak this signal as good as you can get it. If it gives a better quality reading, then I know I'm moving in the right direction, if not I adjust in the other direction. Usually it only takes a couple adjustments like this to find the arc. With a big dish, I've found that often the proper direction for this adjustment is what seems to give you worse signal when you move the mount on the pole, because with a big dish, you are changing the sync as well as the n/s alignment, and you have originally "found" this sat out of sync. However, with these little offset dishes, you "normally" aren't that far off on sync since you've gone to the sat via USALS rather than going to the max signal, so there is often very little adjustment requirred here, and the bumping process I described may not even be necessary. However, if you happen to have a motor that is out of sync from the factory, then this bumping process can insure that you get to the arc properly even if the motor is out of sync. The out of sync thing with these small motors is basically when the motor isn't really aiming south when it's told to go to zero. My motor was off by a couple degrees. This means that when you tell the motor to go to some sat via USALS, it goes to the wrong place, so you have to do the bumping thing to find out if you are on the arc.
I know I didn't explain that very clearly.