[amsat-bb] Antenna relay experiments

[Dave Guimont <dguimon1@xxxxxxxxxx>]

I've been reading the fixed antennas discussions on the reflector with a 
great deal of interest.  It is pretty obvious that many others, like 
myself, are searching for answers.

Antenna construction and testing has been, and is, my main interest in 
hamsats beginning with Oscar 6.  The "garage egineering" and empirical 
testing I've done in 20 years has barely scratched the surface, but I would 
like to get some help with an idea I've been pursuing for several years.

The goal is to develop low cost rotorless systems that perform from horizon 
to horizon.  To that end the best system I've discovered is described in 
two articles in:

http://home.san.rr.com/doguimont/uploads

The information is in quadfil1.zip and collin1.zip.

They describe a collinear J pole and a quadrifilar for 435 mHz.  The J 
covers from the horizon to about 30 degrees, and the quad covers the 
remainder of the sector.  I initially manually switched the antennas, and 
then a friend of mine Down Under wrote a small program that attaches to IT, 
and switches at a preset angle selectable from 10 to 40 degrees in 10 
degree increments.  It works very well on all of the LEOs, and with IIID 
looming it could very well be all the antenna that anyone would ever 
need.  He asked previously to not release the software to anyone, but I now 
have his permission to give it to a few who would be interested in 
contributing performance evaluations on any of the birds, and in any mode.

With the above in mind, if you are interested:

1. Respond to this message directly to me.  RESPONSES TO INCLUDE THE 
REFLECTOR WILL NOT BE ANSWERED.

2. I'm getting old and crochety, and will not get into any sort of a 
harangue about the virtues (or non) of this venture.

3. Respond only if you are sincerely interested in experimenting with your 
own homebrew antennas, or use my plans if you wish.  Homebrew antennas are 
equal to or better than any commercial variety that I've compared them to, 
and part of my goal is to enable newcomers to get on the satellites as 
inexpensively as possible.  I DO NOT WANT PERFORMANCE RESULTS FOR ANY 
COMMERCIAL ANTENNAS.  Commercials don't get your balls in an uproar, I am 
not anti-commercial.  Your contribution is very necessary as many choose 
not to build.

4.  Several experimenters have volunteered in the past to assist me in this 
project.  They will be contacted directly, and depending on the number that 
wish to remain I will distribute the software to several more to round out 
the test group.  I can accomodate just so many (this is my hobby!),
and will limit the software to the first responders.

5.  If you are a convention goer, perhaps we can get together for a cuppa, 
and kick this around.
c:\hamradio\xxxxxxx\relayhelp.doc


            73, Dave wb6llo@amsat.org
                    Disagree: I learn....
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