The is a fallacy here to the effect that non-resonant conductors
will not distort the antenna pattern. Although resonant conductors
are worse than non-resonant, any grounded conductor over 1/6 wl
and an floating conductor over 1/3 wl will affect the pattern.
Some quick modeling with EZNEC will bring you the bad news.
Rick N6RK
K5MLC \(Mike\) wrote:
> Get a copy of the ARRL Antenna book. It has a nice chart to show the
> ungrounded wire lengths to avoid. Each band needs a different length.
>
>>From the book
> "Grounded wires will exhibit resonance at odd multiples of a quarter
> wavelength"
>
> "For example, if you operate only the 14, 21 and 24-MHz bands, guy wire
> lengths of 27 feet or 51 feet would be, suitable, along with any length
> less than 16 feet."
>
>>From looking at the chart, it looks like for 10, 15 and 20 meters that
>> about 27 feet and any length less than 14 feet would be good.
>
> Mike
> AD6AA
>
>
>
> "K5MLC (Mike)" <k5mlc@sbcglobal.net> wrote:
> So, do you mean the insulators should be at 27' or less or more than 27'?
>
> 73 de K5MLC Mike
>
>
> ----- Original Message ----
> From: bill rubin
> To: K5MLC (Mike)
> Sent: Wednesday, July 16, 2008 6:55:24 PM
> Subject: Re: [TowerTalk] another stupid guywire question
>
>
> i would recommend EHS as well. also the rule of thumb for the insulators
> is ~27ft. so i heard. I used and recommend using phillystran (Kevlar
> rope) made for guy lines combined with EHS at the bottom. see more info
> at texastowers.com
>
> 73 Bill N1HWC
>
> see my tower project at n1hwc.com
> _______________________________________________
>
>
>
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>
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