I asked my friend Steve, W3AHL, to help me get a 160m vertical going.
I couldn't stand all the reporting of DX others were doing, so had to get in on
it.
It was during Bouvet Fever and I wanted to be ready.
The process, with not much time to write:
Strung a line between my two highest trees, with a tape measure hanging down
from the middle. Found 65 feet of height available.
Something gave me the idea to NOT short the vertical wires, 450 Ohm window line
in my case, so I could also use the ant as a dipole.
Suggested to Steve that 130' would be a nice top wire, to be hot on 80m.
Quick as a wink, Steve and EZNEC told me that 57' of element and 132' of top
wire would be good,.
I am far too lazy for a radial field, so Steve said use four 75' radials, with
a small loading coil cut to resonate the element at 1.83 MHz.
WOW, with just a little tweaking of the radials and coil, between radials and
shield, the ant came right in!
SWR=1.3, no matching needed.
It's great on 160, with lots of Europe and Australia, New Zealand, and Japan
worked right off.
Too bad about Bouvet!
Eu hit with 100W.
And the icing on the cake, VERY hot on 80m, fed with a little L network.
EZNEC says shorting the element wires is not necessary, proven to be true.
Unfortunately, the top wire is about due E-W, so not the best orientation for
80, but it sure meets the design goal.
EU easily worked on 80 with 100W at 45 degrees off axis.
I'm now building a switchbox to change bands from the shack.
Yes, I now need some Beverages. I have space, but so far inadequate energy.
I know I need the Bev's, because I get emails from people hearing me but unable
to reach me.
I put out 800W on 160, from an ancient Eimac 4-400A, with about 200' of 213
feedline.
And, strangely, it's a great antenna for 10m, at least for local coverage.
SWR is 1.1, with no matching, likely with help from coax loss, but it works
very well for our local chat group!
Thanks to Steve, the best antenna project I've done!
Wilson
W4BOH
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