[antennaware] Linear loading as a trap

[i4jmy@migate.n8it.AMPR.ORG]

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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