[Top] [All Lists]

Re: [TowerTalk] Insulator Placement Clarification

Subject: Re: [TowerTalk] Insulator Placement Clarification
From: Jim Lux <>
Date: Tue, 04 Sep 2007 16:08:22 -0700
List-post: <>
> Well, I asked a question about the first insulator and left out some 
> important informatino.  The 45g tower will support a couple of
> 40 meter beams and 4 or 5 10 meter beams.  Maybe that information will help!
> Thanks a million for the bandwidth!

For that kind of investment, perhaps doing a quick interaction model in 
NEC might be worthwhile.  You don't have to slavishly model the tower, 
etc. in every gnat's eyelash detail.  You just model it as a fat wire. 
Model the guys, with breaks at the proposed insulator locations, and see 
if there's any current in the guys when the antenna is excited.  If 
there's no current, there's no interaction.

But, another approach springs to mind.. why not use synthetic guys? 
Then, it's not even an issue.  With a stack of Yagis for the same band, 
clearly you are concerned about ekeing out maximum performance (by 
whatever measure).  Why screw it up with metal guy cables and using 
"rules of thumb" to try and minimize interaction (where *try* is the 
operative word).  Either you're going to do some sort of trial and 
error, or significant amounts of analysis, or, you're going to try to 
exactly duplicate someone else's (presumably satisfactory) installation.

Jim, W6RMK


TowerTalk mailing list

<Prev in Thread] Current Thread [Next in Thread>