Re: Microwave ovens and Project Phoenix S-band - how can they tell?

"Al" <[EMAIL PROTECTED]> wrote in message news:<[EMAIL PROTECTED]>...

> Just read the articles at seti.org on the ongoing observations
> by Project Phoenix at Arecibo.  All great stuff, but in all my
> years of reading about SETI, I had not come across Microwave
> Ovens as being a major source of RFI.  Yet MOs were
> implicated 3 times in those SETI Institute articles.
> 
> I'm curious:  how are they able to differentiate MOs from other
> users of the 2.4 GHz band?  I know of many people [1] who
> abuse the airwaves by pushing their 802.11b wireless
> networking systems to ridiculously high powers and range.
> Surely these are the culprits of the 2.4 GHz noise?
> 
> 
> [1] http://www.pbs.org/cringely/pulpit/pulpit20010712.html


I agree, I can't imagine distant microwave ovens would actually
generate light that could penetrate the sidelobes of Arecibo.

Since there are no ovens on site, the nearest one must be at least a 
few kilometers away in the nearest town. Fact is that microwave oven 
leakage decreases rapidly with distance. For example, with the maximum 
permissible leakage of 5 milliwatts per square centimeter, at an arms length 
from the door, it would decrease to 1/1000 milliwatts per square centimeter.  
And even the little amount that escapes will not get very far before being 
blocked or absorbed by the various insulating layers and walls of a house.