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Old 09-07-2007, 01:30 AM
Jeff Liebermann
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Default Re: My Biquad doesn't work

Knight <petelarosa@comcast.net> hath wroth:

>Earlier you wrote "Your construction in the photo is totally wrong"


Yep. It's totally wrong. However, it appears that such creativity
doesn't have as much effect as I original assumed. Look at it this
way: Anything is better than the stock rubber ducky antenna.

> I guess it really doesn't matter then does it? Seems to be working
>ok!


Yep. My simulation of doing it the wrong way shows that it works well
enough. You decide if it's good enough for your purposes and if it's
worth your time doing it the right way.

>Can that be? Would it work better the other way?


Yes. The rather high VSWR (impedance mismatch) will certainly have an
effect on gain. If I plug the estimated antenna impedance from:
<http://802.11junk.com/jeffl/antennas/biquad-junk/slides/main.html>
as 58.7 -j106 ohms into a mismatch calculator at:
<http://chemandy.com/calculators/return-loss-and-mismatch-calculator.htm>
I get about 3dB of loss with this mismatch. In theory, you should be
able to recover most of that by proper construction.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

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