Oh, I almost forgot..... coax length!!!!! The low impedance of the ground will
be reflected at the radio when the length of the coax & ground strap, from the
ground rod to the radio, are 1/2 wavelength. This means 1/2 wavelength -without-
consideration of velocity factor because we want a low impedance -ground-. And
this means -- you guessed it -- 18 feet of coax!

18 feet? Are you sure? I thought 18 feet was only a convenient
length for mobile antennas and could never have any electrical
significance.