Last October, I put up four 30 ft tv-mast poles to hold up
the corners of a 160m full wave loop. It was setup as a
140 x 100 ft. rectangle, fed at the center of one of the
100 ft sides. Cheap 'n easy high angle antenna. During
the ARRL 160 m CW 'test I was able to work 48 states and
five countries (including W-K and VE) with 100 watts, over
about 8 hours of fun. One eu QSO, the fellow across the
pond must have had golden ears!
I'd say a horizontal full wave loop might be your ticket
for a domestic 160m antenna. This fall, it will go back
up, but probably at 40 ft instead of 30. Very non-exact,
construction wise. Anywhere from 400 to 500 ft in the loop
is fine. My 480 ft loop, fed with about 70-80 ft of
heavy-duty twinlead had a net inductive reactance at the
shack end across the 160m band, and a resistive component
that varied from about 35 ohms at 1.8 to about 100 ohms at
2.0 mhz. System resonance at the shack end of the feeder
was around 1.7 mhz. My over-designed tuner consisted of a
1000 pf broadcast type variable capacitor in series with
one of the twin-lead feeders that came in the shack window
behind the rig, then a several turns of RG-58 wrapped
around some large toroids to keep the RF off of the shield
and rig chassis. An RF ammeter in the leg opposite the
variable cap made for quicker tuneup.
Side note.. I had hoped that this loop would make a great
high-angle 75 meter antenna by opening up the far 100 ft
leg, serving as a bi-square on it's side. Modeling the
thing seemed to confirm that. The 80m dipole at 40' beat
it hands down at any distance, however. Had me
head-scratching, but it was a joy to have a 'real' 160
meter antenna for the first time in 30 years of hamming!
I should also mention that the big loop is excellent to
switch in as a receiving antenna on most bands. Very quiet
with respect to local line noise compared to my dipoles and
vertical\sloper tries.
73, and CU on top band! - Mark
----------------------------------------
Mark Shaum K9TR
mashaum@fcg.net
Central Illinois Grid EN50
---------------------------------------
----------
> From: Fatchett, Mike <Fatchett.Mike@tci.com>
> To: 'towertalk@contesting.com'
> Subject: [TowerTalk] 160 meter antenna
To: <towertalk@contesting.com>
> Date: Monday, July 21, 1997 2:01 PM
>
> Looking for ideas and quick and easy 160m antennas. I
don't think I
> have enough room a dipole. Not looking for a great DX
antenna. Just
> need to work NA for the NA QSO party.
>
> Mike
> W0MU
>
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