[TowerTalk] Comments by K9YC

[Steve Hunt]

You can then try inserting a choke at the feedpoint in the EZNEC model 
and see how it does indeed change the SWR on the feedline!

The SWR is bound to change under those conditions. If you have a low CM 
impedance back along the coax braid outer surface, which is shunting one 
side of the antenna to ground, the impedance "seen" at the end of the 
feedline is bound to change when you then use a choke to make that shunt 
CM path a much higher impedance.

Steve G3TXQ



On 23/06/2014 05:03, Joe Subich, W4TV wrote:
>
> In fact, get EZNEC or another modeling program that will show you the 
> currents in each segment.  Then play with the length of that third
> wire to see what happens to those currents at various lengths of
> wire ... what happens to "feedline radiation" and how beam patterns
> can become corrupted/skewed.  It's quite interesting and educational.
>
> 73,
>
>    ... Joe, W4TV
>
>