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Old September 30th 08, 03:20 AM posted to rec.radio.amateur.antenna
Owen Duffy Owen Duffy is offline
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First recorded activity by RadioBanter: Dec 2006
Posts: 1,169
Default Going tp put this antenna up today

"Howard Kowall" wrote in
:

Hello All

....
I guess it has it place) I have decide to try something new and
hopefully better.Here it is, the Mystery Antenna,I had all the parts

....

Now, lets see... that the "multi-band wire antenna that performs
exceptionally well even though it confounds antenna modeling software".

Yet another 'magic' antenna who's 'magic' cannot be explained!

Of course the claim is nonsense, the antenna can be modelled in NEC...
just the complication is evaluating an equivalent load in NEC terms for
the TL stubs.

You can evaluate the equivalent impedance of a s/c stub of 16.5' of RG8X
(or whatever you used) using the calculator at
http://www.vk1od.net/tl/tllc.php.

For example Z of s/c stub of 16.5' of RG8X at 7.1MHz is around 2.97
+j64.54, so it acts like a quite lossy inductor at that frequency.

Once the feedpoint impedance is found, the transmission line losses and
ATU losses can be evaluated for a system perspective.

Ask yourself why they choose to not model the antenna. Often, when people
claim that an antenna can't be modelled in reality just don't like the
answers.

Owen