| I’ve seen sites where someone improved on the original design with high-Q coils 
and it looks enticing, but I recall that it wasn’t trivial because the 
distribute capacitance also changed, which led to what amounted to pretty much 
a re-design. The result was apparently excellent, but it wasn’t plug-n-play. 
Kim N5OP 
"People that make music together cannot be enemies, at least as long as the 
music lasts." -- Paul Hindemith
> On Sep 27, 2020, at 2:59 PM, Jim Thomson <jim.thom@telus.net> wrote:
> 
> Date: Sat, 26 Sep 2020 21:10:47 -0400
> From: <john@kk9a.com>
> To: <towertalk@contesting.com>
> Subject: Re: [TowerTalk] 40 meter beam
> 
> <I believe Cushcraft uses 68 turns of 12 AWG wire. There are much more
> <efficient loading coil designs that are also more durable.
> 
> <John KK9A
> 
> ##  https://www.qsl.net/ve6wz/CC_coil.html    Just about anything is better  
> than  68 turns of 12 gauge magnet wire..with turns  butted  tight.. 
> The latest version of the  coil software by  k6sti is called    3.95   
> http://ham-radio.com/k6sti/   scroll to bottom of left side of page.
> Coil Inductance and Q Calculator 3.95
> 
> 
> 
> .75 inch  OD  aluminum  tubing,  like  3003 is  very easy to work with.  
> Mcmaster carr  sells it, and other  sizes.
> 
> Jim   VE7RF
> _______________________________________________
> 
> 
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