As a result of the excellent response to my last message on Rohn 45 64 =
foot Foldover Towers, I ordered one last week and it should arrive next =
week or so. I still have a million questions on lightning protection, =
but when I get through with the Polyphaser book, and have a proposed =
solution, I will post it for comments.
Now I need to get antennas, rotator, and a switchbox on order. Any =
suggestions would be appreciated. I probably will buy the Yaesu =
FT1000SDX rotator and probably homebrew the switchbox if I use a quad =
since I will need 8 positions (I have never seen one with more than 6 =
positions)(5 for the quad, one for 40 mtr inv vee and 1 for 80 mtr inv =
vee and something for 30 meters). I have considered building a vertical =
antenna and if I do that for the low bands, then a 5 position switch =
would be all that is needed on the tower.
I am presently planning to buy or build a 2 element cubical quad with 5 =
bands (10,12,15,17,20) and feed each loop independently through a switch =
box. For the past 21 years I have had a 2 element 3 band (10,15,20) =
quad with better results than my previous tri-bander (Hornet TB-500-you =
don't want one) that I used before that.
Question 1. Does anyone have a computer analysis of a hf two element, =
multiband quad that they could either e-mail me the analysis results =
including spacing and wire lengths for elements, pattern, vswr, input =
impedance, f/b,etc. If a public domain program will run the input data =
and you send me the input file and a few directions that would be even =
better.=20
I will buy the kit from Cubex, use #14 stranded copperweld elements, =
single piece 13 foot fiberglass spreaders, and tune the quad for cw =
operation (but that usually also covers phone bands). I have not =
considered Lightning Bolt or others with Spider Hubs because they seemed =
so flimsey to me.
Question 2. Is there a better way to get 5 bands for dx work other than =
with a quad? This will go up on a 64 foot Rohn 45 Foldover which is =
rated for 135 pounds for the antenna,mast and rotator load. I was =
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