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Re: helix+PrimeStar



I wonder if 2.25 turns is providing the correct beamwidth to illuminate the
dish.  Both of my offset fed dishes needed narrower beamwidth helixes.  My
18 inch dish needed a feed bw of 90 degrees and my latest project a 3ft
offset dish needs a 70 degree feed.  This works out to be a helix with 5 or
8.4 turns respectively.

Lee-KU4OS

----- Original Message -----
From: "Bill Hurlock" <bill@hurlock.net>
To: "'amsat-bb@amsat.org'" <amsat-bb@AMSAT.Org>
Sent: Monday, June 04, 2001 15:21 PM
Subject: [amsat-bb] helix+PrimeStar


> Build a Saturday afternoon helix for my PrimeStar dish. Tried it out
> Sunday morning with mixed results. The 3733 + Myers BAR-B seemed to out
> preform it by about 5db. The helix is a 2.25 turn with a N-N turnaround
> right into the Drake having all the mods into. I still seem to have the
> same amount of fading as the linear feed on the BAR B dish. Well this is
> what Ham Radio is all about....Tinkering and testing new stuff. I will
> say the wind was trying to push the primeStar dish around while I was
> holding it. That solid dish really catches the wind. The elevation
> angles where around 25 degrees when I was testing things. Not 100% sure
> on the squint. I was running back and forth from the BAR B and the
> Primestar 736r in hand HIHI.
>
> --
> Bill
> WA2TQI
>
>
> ----
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>

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