Ok, everyone thanks for all the help.
I rebuilt the antenna from new wire, built a two insulator termination at the
end of the horizontal section where the high voltage is, I rehung the new
antenna so that it doesn't touch anything… and the problem persisted. I then
looked into Tom W8JI's suggestion about a bad lightning arrestor, and indeed
that was the problem. I had blown the little cartridge in my Alpha Delta
lightning stopper.
I don't know why the issue only showed up on a single antenna of the many I
have fed through that device. But it did.
So Tom, thanks in particular.
I did leave the choke balun in place. Who knows if that makes a difference?
Everyone, please listen for the weak signal from Western Colorado this weekend.
KQ0C
Ash
On Nov 28, 2012, at 10:30 AM, "Tom W8JI" <w8ji@w8ji.com> wrote:
> Remove the balun. It's not doing anything for your and is a potential source
> of loss and problems. Coaxial cable is unbalanced, as is a ground-fed
> inverted L. No need for a balun. >>>
>
> Unfortunately, that is not a universally true statement.
>
> MOST antennas are in a "neither" world of being neither perfectly balanced
> nor perfectly unbalanced.
>
> Perfectly balanced would be equal and opposite currents entering and leaving
> each conductor at each end of a balanced line, with equal voltages to the
> world around the line from each conductor.
>
> Perfectly unbalanced would be the same equal and opposite currents entering
> and leaving each conductor (shield and center) at each line end, and zero
> voltage from the shield to the outside world around the line.
>
> Very few antenna systems meet that criteria, although Marconi systems with
> many radials are close enough to be nearly perfectly unbalanced. Significant
> departure from UNbalanced occurs when radial systems are sparse, or
> truncated, or the feedline exits above the plane of the radials. There isn't
> any clear boundary, but a slow system dependent transition from the perfect
> case (feedline exits below the radial plane and an infinite full size radial
> system) to the worse case (a single radial of any design). Even four 1/4 wave
> radials have significant voltage to "ground" at the common point.
>
> Choking impedance required varies with the number, configuration, and length
> of radials and how the feeder is routed and grounded, and in nearly all cases
> a few hundred ohms is enough. An exception might be if the ground system
> common point has abnormally high voltages to earth (for example, a single
> truncated radial) or if the coax is elevated and coupled to the antenna.
>
> 73 Tom
>
>
>
>
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