Date: Sun, 21 Aug 2016 22:27:57 -0400
From: Wayne Kline <w3ea@hotmail.com>
To: "towertalk@contesting.com" <towertalk@contesting.com>
Subject: [TowerTalk] 30 meter rotating dipole.
Never had an antenna on 30 meters and the new little tower I am erecting 74'
has as Skyhawk triband antenna @ 75'
I though I have this old F-12 rotating Dipole EF401 ??? not sure of the # But
Why not a rotating 30 meter dipole 8 ft above the Triband Antenna.
So....... has anybody modified a F-12 40 meter dipole to 30 meters ?
Wayne W3EA
## IMO, a 40m rotary dipole would be far more useful vs 30m. However, it
would be
an easy matter to convert any of the F12 40m rotary dipoles to 30m operation,
but this all
depends on which model 40m yagi u have. The F12 40m linear loaded dipoles
I have use
44 ft long eles. Without the LL wires, the ele alone should resonate aprx
10.7 mhz.
## For 30 m operation, I would toss the LL wires, and replace with a single
dacron .1875 line
on each ele half, to support the ele halves. Where the fiberglass
insulator is located, half
way out each ele half, either bridge the insulator with a piece of strap, or
bridge it with a
U shaped stub. IE: 1-2 inches down, few inces across, and back up 1-2
inchs. Then the ele
will resosnate where you want it, like 10.125 mhz. It should only require a
1:1 choke balun and 50 ohm coax.
the hairpin should not be required.
## If the 40m dipole is the shorter aprx 37 ft eles, same deal, except your
stub will have to be bigger, that or replace the
stub with a small coil. In the case of the shorter 40m eles, 37 ft version,
the hairpin will be required, but smaller than the
oem 40m hairpin.
Jim VE7RF
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