Topband: Quarter wave sloper ?

[Jean-Paul Albert]

Working well but I killed twice the 3 elt 40 m KLM rotator (T2X) with power. Legal US power !

73’

Jean-Paul 

F6FYA depuis son iPhone

> Le 28 juil. 2024 à 06:04, Jim Brown <jim at audiosystemsgroup.com> a écrit :
> 
> On 7/27/2024 6:59 PM, jim.thom jim.thom at telus.net wrote:
>> Quarter wave sloper ?
>> Just to be xtal clear, when I said 1/4 wave sloper,
> 
> Yes, and that's been a popular way to do it. I chose another, and described it. It is, indeed, a quarter wave, and it slopes.
> 
> BTW -- those rods under the tower are an effective earth connection for lightning. But they are NOT a low-impedance path for RF, simply because the earth is a big resistor.
> 
> The only function of an earth connection for transmitting antennas is lightning protection. The earth is a big resistor. The functions of radials are 1) to SCREEN (shield) the field produced by the antenna from lossy earth; and 2) to provide a low resistance path for the antenna's return current. A counterpoise provides only the second function.
> 
> N6LF has been publishing some excellent work on radial systems, describing an interactive research process wherein he models various conditions, then built and measured them extensively, revising his model or modeling different variables, depending what he learned in the measurements, and so on. It is excellent engineering, and has given me many new understandings/insights of why radial systems behave the way they do. Many of us consider it the most important work on LF antennas in fifty years.
> 
> https://www.antennasbyn6lf.com/
> 
> The 2009 series on ground systems and the 2012 series on elevated radial systems are the material I find so worthwhile. Grab them and settle in with a nice Scotch.
> 
> 73, Jim K9YC
> 
> 
> 
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