On Dec 4, 2005, at 12:53 PM, K4SAV wrote:
> If your feedline changes the resonant frequency of your antenna,
> that is
> an indication that your ground radials are insufficient. The resonant
> frequency of a vertical or inv L will change as a function of your
> radials, if you only have a few radials. As you add more radials, the
> resonant frequency will stabilize and no longer move. Your feedline is
> acting as a long radial.
More radials will also make the antenna more efficient, as ground
losses are reduced.
Placing a current choke at the feedpoint should also reduce currents
on the feedline. But radials have larger benefits.
Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr at arrl.net
Quote: "Not within a thousand years will man ever fly!"
-- Wilbur Wright, 1901
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