wrote:

In a ground plane, what dictates the number and spacing of
radials?

The height of the antenna above ground in wavelengths. Yes, at a 1/2
wave
or more up, even just two radials are pretty decent. But at 1/8 wave or

lower, 2 radials are just barely above the "waste of time" level as far
as
reducing ground losses... Take two ground planes. Both are at 20 ft at
the base. Each has two radials. But one is for 145 mhz, and the other
is
for 1.85 mhz. Do they have equal ground losses? Not hardly... MK