On Jun 20, 8:01 am, Buck wrote:
Does anyone know where I might find that formula?

How about a rule of thumb? Using a 2 liter pop bottle, make the number
of turns equal to the wavelength in meters. That will optimize for a
specific wavelength but will render it not very useful for any shorter
wavelengths, e.g. 20 turns is too many for 10m.
--
73, Cecil, w5dxp.com
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