Message-Id: 2838_migate
From: i4jmy@n8it.#nwmi.mi.usa.noam
To: antennaware@contesting.com
Beeing intersted to discover what could be the losses in a linear loading
when used as a trap, I modeled a 3 elements triband yagi antenna whose
elements are very symilar to a KLM KT34 and boom lenght is 5m long.
Results are apparently quite surprising because I aspected much more
losses than a few decimal of DBs.
The gain approaches that of a linear loaded antenna of same size on 20m,
something less on 15m, nearly a net gain on 10m.
Shapes and materials are well defined in my model and do not represent a
possible error, I think, the Q of the capacitors was instead fixed by my
brain to a value of 150 that should be prudential for an air spaced
capacitor.
I'm asking myself if that Q I used for the resonating capacitances is a
resonable value or, if going to a real antenna with plastic spacers and
insulators, that values drops a lot, expecially on higher frequencies, so
vanishing most of the gain.
Is there anyone able to clear my doubts ?
Feel free to point out mistakes if I did any.
73,
Mauri I4JMY
e-mail: i4jmy@migate.n8it.ampr.org
altern. i4jmy@uugate.wa7slg.ampr.org
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