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Re: (meteorobs) RE: sizziling skies report

At 14:32 2001/01/05 +1100, you wrote:
>Could it be that this effect shows up on FM radio as well?

No.  These are very LOW frequencies.  While some believe that there might
be a VHF (very high frequency) component, it would be much too weak to
detect except in *very* rare instances - far less common than the
VLF/electrophonics.  (In the past, several groups thought they had detected
siginals on higher frequencies.  But  the results seemed no better than
chance).

>(I've been told a FM station cannot produce a 
>doppler effect because of its frequency modulation, so it can't be a 
>shifting in frequency by the station).

False.  The Doppler shift is the same.  However, the FM *detector* in a
receiver would not detect it.  (And, because of the constantly-varying
frequency, the Doppler shift would probably be lost in the modulation, even
when beating the incoming signal with a local oscillator).

 >I have also read on the web that a 
>meteor does not produce radio waves of its own. Any comments on this?

If you'll read carefully the Sizzling Skies article, you'll see that the
basic theme of this research is that they *do* produce their own radio
waves.  The question is, how are the produced, and how do they sometimes
produce the "electrophonic" sounds.
There are a number of other reports on this, esp. from the 1999 Leonids in
the Mid East.  I don't have the URLs available right now, but I believe
several are still at
http://www.qsldot net/w8wn/hscw/papers/archive.html#electrophonic sounds
(and the Leonids notes there)  and also http://leonid.arc.nasadot gov    and
follow the links.

To receive something like this would most likely require equipment capable
of receving in the very low frequencies, probably 30,000 Hz and lower.
This is difficult because of the interference from power lines, AC-operated
equipment, etc.  In other words, equipment similar to that used by the
"Lofers" for communications experiments in the 150 kHz range, or (quite
different) by those who like to listen to "sferics" (the antipodal
reflections of lightning strikes and other strange-sounding things).

This could be a very fertile area for experimenting by amateurs, but would
require very tight parameters because of all of the interference possible
from so many other things.  Could only produce usable results during a
shower or at the time of a fireball; would have to be correlated with
visual results; would probably have to be in a rural area, away from AC
power lines and equipment; etc.  But to even narrow things down could be of
help to those few groups in this field (which generally was laughed at
until a couple of years ago).

Shelby

Shelby Ennis, W8WN - EM77bq - KY
                w8wn@arrldot net
              w8wn@amsat.org
   Web - http://www.qsldot net/w8wn/  
                       <><


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