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Old November 9th 04, 01:18 AM
Tom
 
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The NTIA measured a series of microwave ovens as part of interference
testing for 802.11.

Here's a link to the main page
http://www.its.bldrdoc.gov/pub/ntia-rpt/94-303-1/

And a link to the measurement results
http://www.its.bldrdoc.gov/pub/ntia-...03-1/chap5.pdf

Summary of the summary:

Worst-case emissions were near 2450 MHz. Ovens averaged about
+113 dBuV/m, the worst case one was about +128 dBuV/m measured at 3
meters.

dBuV/m is dB relative to a microvolt per meter.

Hopefully I'm not hosed up here, I think +120 dBuV/m is the same as 1 v/m.

That would make these ovens E-fields about -7 dBv/m to +8 dBv/m, or about
0.45 v/m (mean) up to about 2.5 v/m worst case).

-- Tom






"Thierry" - wrote in message ...
Hi,

I haven't find a better ham newsgroup for this question... so sorry if it
is
s bit off subject.

I read somewhere that a GSM 900 MHz produced at electromagentic field of
50V/m (!!) placed at the ear, a 900/1800 Mhe up to 70V/m and a microwave
oven working at 2450 Mhz (850W) up to 80 V/m on top the cabinet.

These values are falses !
If we convert these data in watts, we see that the power radiated is
greater
that the emitter power. Hi !!

More than 100 GSM were recently tested in Belgium by labs and controlled
by
the P&T (IBPT) and confirm that the measured fields, at one or two
exceptions, are BELOW 1V/m.
We are thus well below the energy released by any ham device.

Problem I don't know if the microwave oven value is correct.
Can someone know its EM field expressed in V/m ?

Thanks in advance

Thierry, ON4SKY
http://www.astrosurf.com/lombry