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MicroOven Beacon-WARNING!



>From: "Mark L. Hammond" <hammond@surrealnet.net>
>Do what I did last night.  Turn on your microwave oven, and point your 
>array+downconverter at it :-)
>
>Worked like a charm...I had my 9 year old daughter helping.  She got a kick 
>out of opening and closing the door for me.  She didn't know she was 
>actually doing satellite CW ;-)
>73,
>Mark N8MH

You did what!?

Mark, did you defeat the safety interlocks in your microwave oven?  By law
the oven is suppose to stop generating RF the second the door is opened.
Radiation from an open microwave oven is extremely dangerous!  The RF power
varies by model from 500w to 1400w.  Safe exposure is <1 mw/sq-cm. for
short time duration.  I haven't looked up the FCC exposure standard but
expect it is at least this.  

2.4 GHz was chosen for ovens because it is particularly good for heating
organic tissue {that means YOU!}.  I turns out that human cranial cavity is
nearly resonant at these frequencies {cook your brains quickly};  Eyes are
also particularly sensitive and microwave exposure can cause cataracts.

"If you are going to try this at home" {as the caveat in TV advertising
goes}, keep the door closed and try to detect the weak RF leakage.  I
haven't tried this but there may be sufficient RF leakage to provide a
signal.  After all your 2.4 GHz convertor should be able to detect around
-100 dBm [1/1*10^10 mw].  With a couple feet safety distance {door closed}
that may reduce to -60 dBm [one millionth mw].  I'm not sure what UL and
OSHA say about microwave oven leakage standards, but I would suspect it to
be better than .01 mw [-20 dBm].

DID I SCARE EVERYONE SUFFICIENTLY?  I HOPE SO -- THIS IS SERIOUS!

73, Ed
PS:  I performed microwave energy transmission studies for NASA in the
1970's using microwave oven tubes.  We were able to transmit power over
10-15 miles with 30% efficiency {i.e. we got 300w for transmitting 1000w}.
The study was for a concept to beam solar powered microwave beams to earth
as a source of alternative energy...concept was abandoned due to safety
concerns.
 
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