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2.4GHz Downconverter and Dish



Message text written by "David M. Tipton, PhD"
> 
I have purchased a 2.4GHz downconverter and a 2X3 dish for use with ATV 
Reception.  The person who sold it to me, informs me that using it for P3D 
will be a non-issue as well.  (Evidently, it's very broadbanded).

Anyway, the question has arised in mind, that since this dish is actually 
Vertically polarized (Though capable of 24dbi gain), is it worth my time to

stick it on the sat array for P3D?  Will the vertical polarisation be 
sufficient, or do I need to investigate alternate antennas?

Thanks,
Dave, N8KXA
_______________
Dave:
        Well, my 2x3" dish with a fixed dipole feed (the commercial one
that came on it; no mods) was entirely adequate for 2401 on AO13. It worked
fine with the Drake 2880 converter plugged right into the feed pigtail
right behind the dish. Of course, it worked better with a decent preamp,
but it did work. It oughta knock your socks off on P3D, just the way it is.
Put it up and see what happens!
        By the way, vertical and horizontal polarizaton are relative to the
horizon and meaningless terms for satellites.... the satellite has no frame
of reference. Polarization is either linear or circular. With this dipole
feed, it's linear, which, of course, won't be quite as good as circular,
but the difference probably is not worth the work to go circular. But
linear won't be able to be as wrong as wrong-handed circular, either. Read
the article (part 2 of a series) I wrote for the upcoming AMSAT Journal
(should be out Oct 1) that discusses a little about the vagaries of
polarization on high freqs.

Have fun!

Ed K9EK (ex-KA9LNV)
author/editor "Mode S: The Book"
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