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Re: Useless questions



Original poster: "Paul Nicholson by way of Terry Fritz <twftesla-at-qwest-dot-net>" <paul-at-abelian.demon.co.uk>

Jim wrote:
> sound card  does the digitizing into a .WAV a shareware program
> called SOX converts the format to something useful (i.e.  a text
> file)

Or if you're sensible enough to run a unix, 
$ od -vw1 -tu1 -An < /dev/dsp > my_data.txt

And this is all sounding very complicated. It would be interesting
if there was anything other than a null output from the homodyne,
and it'd be exciting if whatever output there was, was correlated
with either the bps or the RF.  

> Would there be some statistics of the doppler that might be of
> use? 

How about its highest significant frequency component?  If the
topload is surrounded by a 'sphere' of ionisation, then does it
form all of a sudden, when a certain voltage is reached, or does it
swell out and in gradually in time with the RF cycle?  My guess,
from reading Bert's postings, is that it forms pretty quick once
a certain V/m is reached at the surface of the topload. Presumably
the return amplitude will be roughly proportional to the size of
the reflecting part of the ionisation,  so amplitude modulation of
the radar return would be nice to see.  But we might expect the
highest beat frequency from the homodyne output to be related to
the speed of the advancing ionisation, since that's the quickest
moving thing around. Lets see, if the ionisation advances towards
the radar at 3cm per nS, then we'd get a beat component at 1GHz? 
Anything slower than this might be visible on a 1GHz spectrum
analyser hung on the homodyne output (directly off the mixer -
bypassing any filtering).

Guess someone just needs to put a security radar and a specy-an
in a real good faraday cage and point it at a live TC.  Just to see
if there's any sort of meaningful output.  It sounds within reach
when you put it like that.

You never know, maybe you'd find that the breakout scatters the
radar real well, or just the right amount of ionisation around the
topload just absorbes it - neat stealth, eh?
--
Paul Nicholson
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