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Old September 26th 10, 09:31 AM posted to rec.radio.amateur.antenna
Owen Duffy Owen Duffy is offline
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First recorded activity by RadioBanter: Dec 2006
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Default Looking for ideas: 2m double-stacked full-wave loop for SSB

"Stuart Longland (VK4MSL)" wrote in
:

....
Are you intending putting the 2m antenna on top of the pole carrying
the 20m vertical dipole? Do you think they might interact?


I think there probably will be some... but hopefully not a serious
problem since only one will be driven at a time. At the moment I've
got a quarter-wave groundplane and a TV-antenna in _very_ close
proximity (about 40mm apart) so surely any interference I get with the
20m vertical will be minor compared to what I (and the TV viewers at
my QTH) already put up with.


If you want to learn something, make your experiments simple... and that
means separating your experimental antenna from things that will (and
they surely will) confuse things.

....

By the sounds of things... homebrewing a 2m ATU may not seem so
silly... I did make an air-core autotransformer for use on HF which
I'm able to use to tune a short end-fed vertical (actually, a 6' 27MHz
CB whip) quite successfully on 40m... perhaps the same concept will
work for VHF. I was hoping though, if I could hook two loops in
parallel, that would give me 50 ohms... I guess it'll be time for
experimentation.


Firsly, ask yourself it ATU is a common approach, and if not, why not.

Re the unloaded / base loaded 6'whip on 40m , it is unlikely that it is
very efficient, but there is a lesson there, even inefficient antennas
can be used to make contacts... just less of them. Some people use QSOs
as 'proof' that an antenna 'works', whatever 'works' means.


Yep... A lot of people say "Just buy X brand/Y model antenna"... but I
believe in giving the homebrew route a try first. :-) I live to
learn.


That was what ham radio was about once, a dying part of hobby now.

Some also say "any antenna is better than no antenna at all", but if you
are interested in the technology of antennas, you will do better than
that.

Good luck Stuart

Owen