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Re: RE:Re: AIDC Downconverter Survey Results



Look, it's all very simple and we've tried to discuss it here, but some
people can't get it:

1.) There is a FIXED dynamic range to the satellite.  From the beacon to the
noise floor this is about 20 to 23 dB or so.
2.) The proscribed maximum power level is 10 dB below the beacon.
3.) In order to sufficiently copy an SSB signal, you really need a signal
that has a 6 to 10 dB SNR.
4.) Given, 3, sufficient signals are then in the range of about 10 to 15 dB
below the beacon!  WOW.  Imagine that.  Obviously, there was a reason that
the designers and control ops picked this point.  Does everyone think that
the 10 dB point was picked arbitrarily?
5.) A BBQ dish under good squint angles is more than sufficient for
comfortable copy of signals 10 to 15 dB under the main beacon.  At higher
squints, no it isn't sufficient.

There is a fallacy out there that the BBQ dish guys are the ones who are
running the excessive power and clobbering the S2 ALC.  THIS IS JUST NOT
TRUE.  The LOUD guys are all the ones who have the EME setups that use L
band.  It's pretty damn near impossible to run excessively huge U band
signals because of Leila.

I have a BBQ dish and I have asked people to turn their power DOWN because I
could hear them plenty well.  I typically run about 150 to 250 W EIRP into
the bird AND I HAVE NO PROBLEM HEARING MYSELF!  Stop saying that the guys
with the BBQs are causing the problems.  IT JUST ISN'T TRUE!

Jon

on 2/21/03 7:21 AM, kgschaffrath@beckman.com at kgschaffrath@beckman.com
wrote:

> Just what is it about THERE IS ONLY 50W ON THE S2TX AND IT IS SHARED AMONG ALL
> USERS
> that you guys dont seem to get.
> 
> It does not matter if you are satisfied with your antenna or not.  This is not
> HF.  If you run more
> power on HF it dont bother anyone.  If you run more power on the sat your
> taking
> more then
> your share of the downlink power and in some cases driving the AGC higher and
> actually
> taking away the opportinuity of some people to use the satellite.
> I remember years ago...  we use to call these people LIDS.
> I guess with PC nowdays  we try to be extra nice and explain it to them over
> and
> over
> adnausium even if they still dont get 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."


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