Cecil Moore wrote:
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.

So it is your "rule of thumb" that 160 turns would be used for 160m?
I don't think so, Cecil. Six or eight turns on such a form should work
fine for 20-10m.

Dave K8MN