On Sat, 10 Jan 2009 22:40:58 -0600, Its from Onion wrote:
>260 feet of #12 wire suspended at or about 85 feet.
That's fine for 160, but to work most of the other bands, consider
the HyPower loaded 160/80 dipole, then add a parallel 40M element to
it. Feed it with RG8 or RG11 and one of the coaxial common mode
chokes described in
http://audiosystemsgroup.com/RFI-Ham.pdf
For details of the parallel fan, see
http://audiosystemsgroup.com/LimitedSpaceAntennas.pdf and
http://audiosystemsgroup.com/LimitedSpaceAntennasPPT.pdf
Google on HyPower Antenna Company to find them.
This antenna will work VERY well on 160, 80, 40, 30, 17, 15, and 12M,
and will be MUCH quieter than the one you've described. I've even
loaded it on 6M and made a bunch of 2,500 mile contacts with 100
watts! Mine is up 100 ft -- it should also work VERY well at 85 ft.
>65 feet of 600 ohm ladder line feeding the wire directly.
>A mil-spec balun from Antenna Products rated at 2-30M 4Kw PEP
>http://www.antennaproducts.com/BINDEX.htm<about:blank> SM-153.
>50 feet of 9931 coax with a 6" PVC air choke made from 25 feet of
9931 wrapped.
This is NOT a very effective feedline choke. You'll pick up a lot of
RX noise with it. Don't waste your money on any commercially made
balun or common mode choke. The ones you can wind yourself on five
toroids are FAR superior. The problem with twinlead is that you can't
put a good coax choke at the feedpoint, so the antenna picks up noise
from the feedline.
If you're able to use a manual tuner, find a Ten Tec 229 or 238 used
(about $250-$275 for the 229, $300-$350 for the 238).
>Legal limit when needed from a AL-1200 Ameritron.
The antenna I've described can be built in a day, and you can build
three in only a bit more time. So your friends who are helping you
with this antenna can build one for themselves while they're building
yours! You're also going to want to put together a group purchase
for some ferrite cores. See detailed advice on that in Appendix One
of the RFI-Ham piece.
73,
Jim K9YC
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