Antennas that work (for me, at least). [Photos of Real Thing]
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I recently finished the ARRL 160 Contest doing pretty dang well
(I think so, at least) with just small, general purpose antennas!
Look at the actual photos for an idea of how it
goes up , but
a line drawing might be a good start. It is a folded dipole, using
#12 THHN stranded, and 300 ohm twinlead feeder. I guess it
makes a Multee (of sorts)or a Tee- but instead of using 450 ohm
twinlead for
the whole thing, I used feeder I had on hand.
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Any Length 300 ohm
Try to keep as much of the twinlead vertical as you can. My config. had
about 40-45' vertical twinlead, which isn't too bad. In effect, what you
are creating is a top-hat loaded vertical for 160. See below for more
details on construction.
Take the 2 sides of the twinlead, tie them together. Drive an 8' Ground
rod near the end of the twinlead, and attach a clamp. Run RG/8 from a Tuner
in the shack to this rod, attach the shield to the ground clamp. Solder the
center conductor to the twinlead, tape liberally. Tie as many long radials
as you can to the ground clamp, and you are ready to roll on 160.
NOTES:
-My antenna was resonant about 1.790, and I trimmed about
2 feet off the antenna - bringing it to 1.820 or so. However - I wanted
the ability to move a few kHz, and this antenna had a BW about 5kc 2:1SWR
point. SO - I used a standard Homebrew Tuner (L-Match) and was able
to tune it in seconds.
-This antenna can be used on 160-10 as a folded 132' dipole, if you add a
4:1 balun before bringing in the coax to the tuner. Even folded, it seems to
do very well, and it ALMOST seems to have gain on 40m when in this config
since the dimensions are CLOSE to that of a bobtail curtain (tho feedpoint
matching and impedance are off. . .)
-This does hear very well. The majority of
the takeoff component seems
to be vertical, thus it does pick up a lot of QRN and other noise. However -
if you don't have the space or $$$ for a 133' Vertical, or need something
quick to toss up for the band - try this.
-#12 THHN Stranded (colored jacket) is about
$15.00 a 500' roll at
most major home-improvement stores, which gives you more than enough
to construct this and a few 100+' radials.
-Finally, it got me 47 states, All provinces (xcept YUK/NWT and AB) and 10
countries. I worked ~100 west coast stations, and a great number of lower-
power entrants.