Ray Collins wrote:
20 meters. Is it just like AM tower arrays, ground radials as long as
the tower is high at every degree of the compass?

If it were me I'd hang 3 separate dipoles, inverted vees or quarter-wave
slopers off of the tower. The tower shunt feed scheme works fairly well
on 40/80 but I've never had much luck at 20 and above.

My 2c.

-Bill