Answer below - de N4KG
On Wed, 08 Oct 1997 09:13:02 -0500 "Kris Mraz, N5KM"
<mraz@aud.alcatel.com> writes:
>Jonathan Starr wrote:
>>
>> I want to insulate the top sections of guy wire (1/2" for
>> 100' of Rohn 80) for my new tower and need to know what
>> lengths to use. The old ARRL handbook says 24' to 29', 39'
>> to 40', and 57' to 58' are non-resonant.
>
>Question:
>With an antenna like a 4 square you simply "float" the other three
>verticals in order to get them out of the picture while you're tuning
>the 4th vertical. These three floating verticals are almost exactly
>resonant with the one you're interested in. Why is it these near
>field resonant structures don't matter in this case but are highly
>unwanted in the case of guy wires?
>
>--
>
>73
>Kris N5KM
>mailto:mraz@aud.alcatel.com
The QUARTER WAVELENGTH verticals are NOT self resonant
at the operating frequency. It takes a HALF WAVELENGTH resonance
to couple into other elements.
de Tom N4KG
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