Just finished a "Long Tom" Cantenna, built to see whether longer then
1 wave length wave guide wi-fi antenna was useful.

The Cantenna is two wavelength (that is calculated wave guide wave
length) long. For a 3 3/8" I.D. tube that is a 227.220 mm (8.915")
wave guide, so twice that in length for a channel 6 antenna. I also
added a 45 degree "funnel" which has a large diameter of twice the
tube diameter to the front of the tube that is not included in length
calculations..

I have only a software utility called "wavemon" (linux) to test with,
but receiving a signal from a selected wi-fi net antenna about a mile
away, I was getting a reading of 2 - 5 dBM on the old one wave length
antenna and 7 - 9 on the new (long tube) version. Regardless of what
the reference numbers approximately twice the received signal as the
old antenna.

Transfer speeds seem commensurate with the speed difference. From
occasional to pretty regular :-)

I wonder about 3 times? Or even 4 times....?

But I think I mentioned, someone gave me a 36 inch dish that I'm also
building. Just mentioned it to my wife and she said "WHERE do you
think you are going to put that?"

It may be that erecting it is going to be more of a problem then
building it :-)

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)