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@audiosystemsgroup.com> a écrit :
>
> On 7/27/2024 6:59 PM, jim.thom jim.thom@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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