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Re: dish for sale (again)



> I've got a couple of primestar (36"x26") dishes for sale....

Oval dishes have the potential to use only a simple $50 TV rotator for a
fully remote controlled AO-40 one-motor Tracking system.

Simply point the TV rotator's axis at the north star.  THen you don't need
any other elevation system.  The simple TV rotator can follow AO40 horizon
to horizon!

As was pointed out in this months QST, AO-40 is always within +/- 8 degree
of the Geostationary TV satellite ARC.   The oval shape at 2.4 GHz
probably  has about a 20 degree vertical beamwidth  which never needs any
vertial adjustment.  THe horizontal beamwidth is about 10 degrees.  But
you just swing the TV rotator east to west to find the bird.

This should work fine for a good low-noise system.

If you need more gain, make the dish WIDER, but not taller. This way you
still wont need  an elevation controller.  See my sketch on my AO-40 web
page:

  http://www.ew.usna.edu/~bruninga/ao40ant.html

de WB4APR, Bob


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