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ikarus1
Premium
join:2002-10-23
Urbanna, VA

reply to drjim

Re: Found it!

said by drjim:
Just a comment on Discone antennas....They're really bad! ZERO gain, vertical polarization, and usually multi-octave bandwidth. Good for scanners, and Amateur Radio VHF/UHF when it's all you can put up, but that's about it.
drjim

Yes these things are true. I do believe there is a bit of gain over a dipole but not more than 3 dB. Still running sims.

The nicest thing about this antenna (discone) is the fact that you get out pretty nearly what you put in. It is extremly efficient and exhibits a *VERY* low SWR across a 10:1 frequency range. That means one designed for 2.4 GHz will work *EQUALLY* well on 5.8.

This antenna is not a good design for PtP work. It is a darn fine design for *REPEATERS* and *INTERCEPT* work, and that means it is an excellent design for a laptop clip on antenna. There is a second design which is good for a clip on but it will not work *BOTH* bands. I will make one of those when time permits...

I just built another one today and took pictures. I did the template and will put together a web page on it before next Monday, Ryan... "Check is in the mail."

-m-
[text was edited by author 2002-10-30 00:03:11]


ikarus1
Premium
join:2002-10-23
Urbanna, VA

said by ikarus1:
said by drjim:
Just a comment on Discone antennas....They're really bad! ZERO gain, vertical polarization, and usually multi-octave bandwidth. Good for scanners, and Amateur Radio VHF/UHF when it's all you can put up, but that's about it.
drjim

Yes these things are true. I do believe there is a bit of gain over a dipole but not more than 3 dB. Still running sims.

The nicest thing about this antenna (discone) is the fact that you get out pretty nearly what you put in. It is extremly efficient and exhibits a *VERY* low SWR across a 10:1 frequency range. That means one designed for 2.4 GHz will work *EQUALLY* well on 5.8.

This antenna is not a good design for PtP work. It is a darn fine design for *REPEATERS* and *INTERCEPT* work, and that means it is an excellent design for a laptop clip on antenna. There is a second design which is good for a clip on but it will not work *BOTH* bands. I will make one of those when time permits...

I just built another one today and took pictures. I did the template and will put together a web page on it before next Monday, Ryan... "Check is in the mail."

-m-
[text was edited by author 2002-10-30 00:03:11]

Well I was wrong ang Jim was right. The gain on a discone is somewhere about 1 dBi. The radiation pattern looks a whole lot like an apple. Great match, meaning very low SWR but other than that, I have removed the model from the site as I have come to agree with Jim. It's a bad antenna for wireless data purposes.

-m-
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