Topband: Folded Unipole vs Series Fed Vertical

[Tom Rauch]

Hi Herb,

>  Well based on a paper presented at a recent NAB convention several BC
> design engineers have blown away those claims. 

This isn't the first time the false claims that folded elements offer 
efficiency advantages has been reputed. It probably won't be the 
last because the claims of efficiency improvements, even though 
incorrect, promise something for almost nothing. 

Things that promise something for nothing tend to live on and on, 
despite being disproven time and time again.

There is absolutely nothing to be gained, except an impedance 
change. There isn't even much of a change in lightning protection, 
since the bulk of energy in a lightning strike follows the "skin" of a 
conductor...and that winds up being the cage! The tower sits nicely 
in what amounts to being a Faraday cage, all shielded and 
protected from the bulk of energy in a lightning stroke. The bulk of 
energy in a strike would simply flow through the skirt and the feed 
system connected to the skirt.

The worse damage I've ever had in a lightning hit was with a shunt 
fed tower! It was my own unvarnished ignorance to think the 
grounded radiator protected the equipment. 

> be a waste of time.  Have a look at the tests and arguments and let me
> know what you think.  The paper is available for download at:

That web address didn't work when I attempted to invoke it. 
73, Tom W8JI
w8ji@contesting.com



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