> with the top guy at the 50 foot level. I wonder if I could
improve the
> signal from this antenna by substituting
> 4 20-25 foot lengths of wire attached to the antenna at
the top guy points
> with guy rope the rest of the way to the guy
> anchors?
That's the general idea, but I would model it Steve. The
goal is to have the highest net or effective current over
the largest spatial or linear distance possible.
It always comes down to the ampere-feet for a given applied
power. The longer the feet and more uniform the current, the
lower the current (and loss) is for the same radiated power.
There will be a compromise in top load wire length that
results in the highest base impedance (lowest ground
connection loss) without the current in downward sloped
loading wires canceling upwards flowing current.
If I was designing a vertical like that, I'd put a GOOD trap
between the top of the antenna and the hat wires. The trap's
residual inductance on 160 would flatten current in the
vertical making it more uniform with a smaller hat size.
You'd still have 80. Loss in the trap would be negligible on
both bands. The antenna would be more reliable, and work
just as well as the fuller size noodle.
I think the problem is the bologna fed to us over the years
makes us actually like poor designs. For example we are sold
linear loading or mechanical nightmares when something
smaller and more reliable would work just as well or better
electrically. We like full size elements when a properly
loaded half-size element can be just as efficient.
N7JW and K7CA have the right idea with 160 antennas. You
might do a search and look at them.
73 Tom
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