[South Florida DX Association] 160-meter antenna

[Dave Novoa]

Hi, fellows:

Thanks to all who replied to my inquiry on a city-lot 160-meter antenna. I got suggestions, links and a variety of information from both the FCG and the SFDXA.  It pays to belong to groups like these!

For those who inquired, this are my "working conditions".  I have a 70-foot cranck-up tower, topped by a 4 element 20 meter yagi (34-feet boom), and 10' above it  a 2-element 40-meter Cushcraft shorty. The tower 3 - 8-ft ground rods, plus a well pipe and two other ground rods, all tied together with heavy cooper wire.  The tower also has 16 ground radials, buried 3-4 inches,  four are 130 feet long, the rest 70 feet.

Last year I installed an inverted L, 125 feet long, using 300-ohm twin lead, both ends tied up.  The vertical portion was about 45 feet, the rest horizontally, dropping to about 25'.  I could not get a 1:1 match, not even using a Palstar AT1500CV tuner.  Even do, I worked 8 countries (USA, Caribbean and ... Ducie Island!)

I took down the inverted L, and for 4 days last week, my brother KP4MS and myself worked on a shunt-fed system.  We tried all possible dimensions, heights, separation, one-wire, five-wire cage, gamma and omega matching systems, but  nothing --not even close to a 1.830 MHz match.

We then tried a wire vertical, hanging a 68' wire from a bracket about 5 feet away from the tower. Nada.

Based on recommendations, tomorrow afternoon I will try  an inverted L, 135 feet long, with a parallel variable capacitor. For receiving, I will build a small loop made of coaxial cable as per N8PR, and connected to a pre-amp.  Let's see what happens, I'll keep you posted.

My intention is to get on the 160-meter contest later this month, and before the winter ends, work the 92 countries I need for a 160-meter DXCC. Wow!  I already have more than 100 "entities" on 10-15-20-40 and 80, just waiting for a few QSLs on 80 to apply for my 5B-DXCC plaque.  

Again, TU guys.

73,

Dave 
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