[Moon-net] metallic pool or glass fiber pool ; that te question

[vladimir.masek at volny.cz]

Hello,
sri, just to drop a pesimistic note to provoke, hi.
By my guess N=10 is not enough to compare statistically WSJT signal to
the wide-band sun noise.

73,
Vlada
OK1DAK/OK1KIR 


----- PŮVODNÍ ZPRÁVA -----
Od: "Edward Cole" <kl7uw at acsalaska.net>
Komu: "SM5LE" <sm5le at telia.com>, "MOON_NET" <moon-net at list-serv.davidv.net>
Předmět: Re: [Moon-net] metallic pool or glass fiber pool ; that te 
Datum: 1.7.2008 - 12:38:51

> At 01:37 AM 7/1/2008, SM5LE wrote:
> >Hello
> >
> >
> >
> >Just finished measurements for metallic pool versa
> >isolated, glass
> >>fiber pool , to see if  I could fine any influence.
> >>
> >The results you find here:
> >
> >
> >
> >  http://web.telia.com/~u14901544/
> >
> >
> >
> >Results: the sun noise was 0.2 dB worse (less) with
> >metallic pool
> >>and echo's was 0.8 dB worse (less) metallic pool.
> >
> >Those results go for my 2.2 m dish.
> >
> >
> >
> >73 Sven SM5LE
> >
> >_______________________________________________
> >Moon-Net posting and subscription instructions are
> >at
> >>http://www.nlsa.com/nets/moon-net-help.html
> 
> Very interesting study.  You ask why the WSJT echo
> peak is in a
> different focal point from the peak sun noise.
> 
> Here's a guess:  I note that the echo has several periodic
> peaks as
> focal distance changes.  Could that be because of a
> standing wave
> formed by reflected power from the dish?  Since WSJT
> is single-tone
> SSB (essentially a changing freq carrier - FSK) the
> WSJT signal is
> coherent while sun noise is incoherent or random noise.
> The SWR
> effect is not seen on sun noise perhaps because of
> the nearly
> infinite range of frequencies in the complex wide-band
> noise?
> 
> What do you think?
> 
> 73 Ed - KL7UW
> I would like to see a comparison of tripod feed support
> legs vs. non-mettalic.
> 
> 
> 
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