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Re: receiving system design tradeoffs

on 2/6/03 3:28 PM, Frederick M. Spinner at fspinner@hotmail.com wrote:

> I'm sorry if I've caused people to "lose faith" in AMSAT.  But I'm trying to
> preach physics here.  Reality.  I'm truly sorry that we've all
> bought so many of the BBQ's for AO-40 and they are not adequate.  But
> physics say they are not really adequate.

I guess Fred that "adequate" means different things to different people.  I
don't consider a dipole at 20 feet adequate for HF.  A lot of guys do.

Again, if one can hear themselves at a level 10 dB below the beacon and be
comfortable with it and how well they hear others then who the heck cares
what antenna you use.  I've never argued they are optimal. And I have stated
numerous times that my setup is a start and not an end.  I plan on improving
it, but it's a start.

You compare guys putting up 20 foot yagis and not big dishes.  Consider that
the large 22 element KLM 2m yagi and the large 40 element KLM 432 yagi have
a combined wind loading of about 3 feet.  A 3 foot dish has over 7 feet!
Yes, like you said, you can avoid some of that by pointing it straight up.
But then there's the time that you forget to park it and leave for the
weekend and along comes a windstorm.

Again, I encourage ANYONE to get on and try with whatever they have.  Not
everyone on HF has 4 stacked 20 meter monobanders on a rotating tower.  Not
everyone has to have a 4 or 5 foot dish to have FUN on AO-40.  This is a
hobby, the purpose of which is to have FUN no matter how you define it.


Jon Ogden
NA9D (ex: KE9NA)

Citizen of the People's Democratic Republik of Illinois

Life Member: ARRL, NRA
Member:  AMSAT, DXCC

http://www.qsl.net/na9d   <- Updated on 1/22/03!!!

"A life lived in fear is a life half lived."

Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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