[TowerTalk] 2 Element Parasitic Vertical for 160M

[Stan Stockton]

I have a shunt fed tower which is 70 feet tall.  It is 45G and has a 6L 20 on top with a 65 foot boom.  It also has a 5L 15M Yagi with something like a 34 foot boom on the side at about 35 feet.  

For the purpose of modeling the antenna with a reflector 100 feet behind it, I just put the DE in as a 18 inch diameter, 124 foot tall vertical.  The actual reflector I have up is a T shaped element that is 100 feet vertical and 36 feet on top (18 feet either side of the center of the vertical part.  This element is #18 copperweld.  I have it shown over Real/Mininec ground and it shows 5.37 dBi at 1.825.  The  driven element and reflector have a decent ground system tied together in the center with a bus wire - something like 100 radials under each.  

Am I missing something in the way I am modeling it or should I expect to see the results shown by the computer.  I am suspicious of the model since I can change the vertical portion of the reflector to #10 wire instead of #18 wire and the max gain moves up about 40 khz.  I would have thought it would have moved it down some?

I put the reflector back up over the weekend and am going to re-do the shunt feed on the tower but wanted to make that reflector element whatever length should be best first.

If anyone out there knows how to model this thing properly, I would appreciate some help.

Thanks...Stan, K5GO