On Oct 20, 2005, at 11:42 PM, k4sb at bellsouth.net wrote:
> Oh, one thing I forgot on my posts about the Delta Loops is that they
> MUST be fed 17.5% up from either of the
> sloping triangle legs. They'll take a direct 1:1 balun at that point.
> Forget that end of leg or bottom of horizontal feed.
AH! I had assumed we were talking about horizontally polarized delta
loops. I hadn't considered those that were vertically polarized.
> Also, you do NOT have to make all sides of the triangle equal.
The gain of the loop is related to the enclosed area. The more equal
the sides (and the more sides) the better. Circular would be best.
> You can
> stretch out the horizontal leg by
> 25% with no ill effects. And, if you use insulated wire on 40, plan on
> that making the antenna resonant about
> 50 kHz below where you want it, so compensate.
>
> Just for interest, that works out to be 100 kHz for 80, and 150 for
> 160.
I've used the formula 1005/f with good success on 10 and 15m.
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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