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Subject: Re: Any ideas on measuring radiation in the home ?
X-Newsreader: Microsoft Outlook Express 5.00.2919.6700
Date: Mon, 07 Oct 2002 17:33:31 GMT
NNTP-Posting-Date: Mon, 07 Oct 2002 17:33:31 GMT
Organization: AT&T Worldnet
Can you explain the effects. Is it noisy reception or clearer reception or
fade or complete saturation (ie. Null ) ?
"Dave Holford" wrote in message
> News2020 wrote:
> > I did some surveying around the house :
> > I find that the recessed ceiling lights and HVAC sheet metal ducting
> > inlets/outlets show directed antenna patterns - single lobe, two lobes,
> > etc - when circled by an AM radio receiver (there is a null when you
> > the radio antenna directly at it). This may indicate some radio
> > coming from them.
> > Also, the walls seem to be showing grainy noise (the signal is
> > overwhelmed by the noise) in certain well defined regions - eg : one
> > straight line along a bedroom wall at 2 feet height; both sides of the
> > toilet tank in one bathroom; one side of the toilet wall; a diamond
> > region over the towel rack that extends up and down along a straight
> > one corner of the kitchen stand showed really strong interference; one
> > vertical line along the living room center wall; the fire-sprinkler pipe
> > the basement; the mains switch box showed strong noise, etc.
> > The reception in the home general area itself seems to be directional
> > twin lobes in the horizontal and vertical directions (this must be as
> > expected).
> Did you really not expect metal objects and wires to modify the
> radiation patterns/signal strength levels of electromagnetic radiation?
> It's simply amazing the effects of house power, telephone, video,
> plumbing, HVAC etc. can have on radio signals. And, if you are one of
> those lucky? people with metallic foil backed insulation things get even
> more interesting. A basic understanding of electromagnetic principles
> will help your paranoia. The effects can be even more amazing if the
> joints, i.e. in the HVAC, are corroded.
> I used to use a coffee can and a piece of aluminum foil to demonstrate
> this sort of thing when I taught Ham radio courses.
> One of the best personal demonstrations I have ever seen was placing the
> TV antenna under a carpet and watching how the signal changed as people,
> and even the cat, moved around. (Yes you used to be able to purchase
> flat TV antennas to put under the carpet, but I made my own).
> Parking a car near the end of an outdoor antenna can also have amazing
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