> Tom, W8JI wrote:
>
> "With that in mind, I'd rate a linear loaded (helical loading) antenna
> dead last." ========== I consider a linear loaded antenna to be a
> conductor formed into a hairpin type of configuration, not a conductor
> wound helically for any of its length
We certainly have some vague or nebulous definitions in common use
Earl!!
Even if we are talking about linear loading as a folded section or
hairpin, and not a continuously wound linear-loaded vertical element,
placement of the loading hairpin and how it is folded greatly
determines the effective loading location and from that the loop
radiation resistance.
Worse yet, "hairpin linear loading" is far overrated in performance.
With a certain overall physical length, we need a certain reactance
to correct power factor at a given location in the antenna. The
lowest loss always occurs with the highest Q of correct reactance,
and that is best obtained a conventional well-designed lumped
component.
For example, the Q of a 400 ohm reactance with a #14 folded wire stub
is much less than 100. I can easily obtain a Q of 300 with the same
size wire in a conventional coil.73, Tom W8JI
W8JI@contesting.com
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