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Re: AO40 dish



Actually, I'd be interested in the Linux version.  I keep boxes for both, 
and would dump Windows entirely if I could.

One other thought/question I have is this:  "Has anyone used JT44
through AO-40, particularly during bad squint times?"  Since it
in theory can copy down to the negative SNRs, this might be another
alternative.  Certainly for those of us who are very rusty at our CW.

Maybe the idea can be taylored to a weak signal satellite modem...

As far as not having TVRO dishes available in Europe, I feel for you.  They 
are generally free or very low cost now in the US, and readily available.  
However, after looking at them, it shouldn't be too difficult to build up to 
about 15' diameter stressed frame dishes, and
for EME this could be better as the dishes could be made deeper than
TVRO dishes for better sidelobe performance.


Fred W0FMS

>Hi Fred et al
>
> >  Actually, I've wondered if any of the amsat-bb bunch has tried
> >  a JT44 QSO with a 7.5'-14' dish with the 25W or so that many have
> >  for the AO-40 1269 MHz uplink?
> >
> >  My understanding is that 100W to 10' is barely adquate for normal CW
> >  EME on 1296 MHz.  JT44 should add 6-10 dB to this bringing that type
> >  of dish and power level to the realm of possibility.
>
>In last months 70cms and up EME newsletter there is a report of an EME
>QSO between K2UYH (10m dish) and an OH3 who was using 40W to two long
>yagis. Since the polarisation for EME on 23cms is circular, there was a
>presumed 3dB loss there.
>
>I have been asked by HB9Q (http://www.hb9q.ch) to do a JT44 test on
>23cms. They have 400W to a 15m dish (!!!) and are very kean to test
>with satellite class stations. My 23cms system is 100W and a linearly
>polarised 26ele yagi.
>
>I would, except that I use Linux not Windows, and I don't have a sound
>card to radio interface built yet. I am currently writing JT44/FSK441
>for Linux and so that may happen soon. I may pick up an interface at
>Weinheim this weekend.
>
>For those interested, my JT44 for Linux is within 3dB of the
>performance of the "real" WSJT, not bad for only one day tinkering with
>the receive side ! The transmit side works a treat.
>


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