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Old July 23rd 07, 05:57 PM posted to rec.radio.amateur.antenna
Allodoxaphobia Allodoxaphobia is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 148
Default Malfunctioning homebrew field strength meter

On Mon, 23 Jul 2007 07:25:15 -0500, amdx wrote:
I built the circuit from the page below.

http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm

The I get 0v out when held near my wireless router, if
I put it near the microwave oven, the high input impedance
meter bounces up and down between 7mv and 80mv and
everything in between.


Don't treat the microwave oven as a "steady source" for RF. There is
usually a rotating "stirrer" in the waveguide entrance to the cooking
chamber. This is engineered to more evenly distribute the RF energy
about the cooking chamber -- eliminating (hopefully) hot and cold spots.

You may actually be seeing peaks and nulls as an artifact of this design.

HTH
Jonesy
--
Marvin L Jones | jonz | W3DHJ | linux
38.24N 104.55W | @ config.com | Jonesy | OS/2
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