Well, the antenna is kind of odd.
It's an inverted Z. That's right, Z not Vas in Zebra, as in victor.
I put a 178 feet long center fed antenna fed with 450 ohm ladder line in a
130 foot space. I hairpined the ends back to the bottom corners of the
house roof. That extends the antenna so it will radiate on 160, and I have
40 feet of lader line raped in a horizontal square around the shack before
it goes out the wall. When I cut that part out, I loose 10 DB of signal on
160. Tested and tried that one out.
So as you can see, I violated lots of good antenna principals.
Unfortunately, I live in a 112 by 44 feet city lot, rather than in the ideal
plane where antenna theory is created.
I only have room for one antenna, and I run 160 through 6 meters with this
wire. Every year I talk about taking it down and trying an ultra-lite, but
then I work Wales from Wisconsin with 100 watts of SSB, or a zl1 on 12 meter
CW, and I say "what am I thinking" and keep this old thing up.
The reason for the 178 feet length, is an old article, where a guy modeled
antenna lengths, and found that 178 feet is the best length for an antenna
to be used on 160 through 10 meters, you get some gain on some places, and
some loss on others when compared to half wave dipoles on those frequencies,
but 178 feet is the best compromise length.
Anyway, I hope it's 178 feet. It started at 200 feet, but the packer game
was on, so we tied it off, and estimated the length to trim later. The
Packers won, and the test contact was a ja1 on 10 meter phone, so we shut
the radio off and turned the game on. That was in maybe 1990, and all I
have done since, is installed a pulley to drop the center if I have to
re-attach the twin lead, which we had to do once.
Haven't even changed the UV resistant line either. Maybe it's bad luck to
mention that. Thank g-d for the city's tree next to the street. All they
ask is that I make sure the line isn't tight enough to hurt the tree. In
the republican suburb to the west of us, they say people are "girdling the
tree" and make them take down their antennas and pay a fine. Here they ask
if they can replace your rope for you.
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