[Elecraft] OT: Vertical doublets (was: Home made Sigma-GT5 & KRC2 or SGC?)

[JAKidz]

> Original Message From Don Wilhelm [mailto:w3fpr@isp.com]
> The answer to your question does not have a simple answer.

Dang. 
 
> L B Cebik's 44 foot length is chosen because of the single lobe
radiation
> pattern for all bands 40 through 10 - LB assumes (correctly) that any
> impedance can be matched by some method.

Understood. I'm aware of other arguments that this design is very
inefficient because of tuner loss. Translating from feedpoint impedance
calculated by a program such as Multinec to a tuner and what is
matchable and what isn't with the KAT100 is an area I don't understand
(yet).

> A 44 ft dipole is not resonant on any ham band, so your question about
> high,
> low resonance does not compute - it is in the class of a non-resonant
> antenna.

Sorry for not being clear. I meant that given the effect of size on
feedpoint impedance and ultimately the tuner, how should the structure
be sized, the reasonance point for a smaller structure being higher
frequency and a larger lower frequency. Playing with Multinec, it looks
like the higher angle lobe that appears on 10 m with a 44' foot vertical
doublet is reduced with a shorter hatted doublet. It looks like the
physical structure of the Sigma 5 is resonant toward the higher
frequency size with matching done at the antenna feedpoint. Is this
still the design goal if ladderline is used and matching is by the
KAT100 at the transceiver feedpoint?

73,
John K7JG.