Ben Kochie wrote:
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> just so you know, pringles cans are not really useable for wireless, their
> diameter is too small.
> 
> this web page has a decent little web calculator to help you determin the
> effectiveness of a can-style waveguide antenna.
> http://www.turnpoint.net/wireless/cantennahowto.html
> 
> anything with a diameter under 6.1cm will be too small.  and the site
> recommends a 7.2cm diameter.

Some of the numbers that the calculator come up with don't seem quite
right. The one that jumped out at me was the 1/4 Guide Wavelength. It
recommends placing the center of the connector and thus the antenna 
around 2.5 inches from the back of the can. The figures I've always 
seen used are just under half of that.

For 2.15 gig HBO receivers we used 1.2 inches for both the antenna 
length and the distance from the back of the can with 4 inch diameter 
cans. For 2.4 gig I'd start with figures about 13% shorter. The ones we 
made for 2.15 gig work fairly well unmodified but did work better after 
shortening the dipole by about an eighth if an inch.


-- 
Bryan Halvorson
bryan at edgar.sector14.net