[TowerTalk] 80M antenna wire size

[Paul Christensen]

>> What I HAVE done (about ten years ago) was to add a second #10 THHN 
>> to my Tee vertical for 160M, spaced roughly 8-10 inches from the 
>> first, wired in parallel top and bottom. 

I use "LadderSnaps" to create a thick radiator.  Although LadderSnaps are used to make 600-ohm open line feeders, they work well for this purpose.  Simply tie the two conductors together at the top and bottom.  

My 160m T is 100 ft high with an 80 ft. flat top.  Next season, the flat-top will increase to 120 ft. where RF current magnitude is uniform across the entire radiator length with a slight current peak half-way up.  

I initially selected an 80 ft top because it made matching super easy.  The base Z is 50+j200 and only requires a series capacitor to achieve a 1:1 SWR.  The series cap will be replaced by a low-pass L network as the R value is expected to rise up to about 65 ohms.  Resonance presently occurs at 1500 kHz but will shift down to 1400 kHz when the flat-top length increases.  Easy to match with a low-pass L network.

Paul, W9AC