In a message dated 11/17/98 12:42:45 PM Eastern Standard Time, k2av@qsl.net
writes:
<< What is the "best" effective location for the loading, other than at
the ends? What is the effective location for the loading on the F12
design? >>
You can't "load" the end of an antenna, however you can put a capacity hat
there, which is a different critter... Do a web search on mobile antennas for
the optimum placement of the loading coil... Also, the ARRL antenna
compendiums has good stuff on this... The low efficiency of mobile hf antennas
makes getting it right crucial and the mobile gang has done considerable
research on this... That information is directly applicable to other antenna
types...
Force 12 uses critically coupled and reactive antenna elements, in a variation
of an open sleeve coupling, along with forward stagger in the multiband
versions, not true "linear loading"... Loading this design is going to be a
real research project... I would be inclined to leave em alone as the antennas
work as well as any other yagi for the same boom length...
Denny
(There Tom and Natan... I defended your design... Mark it on the wall... in
ink! )
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