At 06:40 PM 7/21/97 -0500, you wrote:
>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
>>
>> --
>>
>
For 2 years, I have had up a horizontal loop which was 1150 +/- a few feet,
fed with
50 ohm coax into a 4:1 balun at the feedpoint. I used an mjf analyzer to
get it
trimmed right for all the hf bands. Turned out to be pretty decent. It
resonated
at 1780 or so but 80 - 10 meters were perfect match without a tuner.
Infact, I
beat out a couple of guys with small tribanders at 40' on 20 meter pile ups
running
100 watts. However, I now have a dipole for 160 up at 90 ft and I do have
to say
this thing wins hands down for stateside. Just put up an inverted L, jury
is still
out till cold wx on that one. 73......Steve
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