Just cusrious...

What happens if you pipe the output of one radio in to 2 different
amplifiers, and then take the output of the two amps and send them to
two identical vertical antennas spaced a half wave apart and with
equal length feedlines from the amplifiers.

Will the output of the two amplifiers add together in directions where
the signal is in phase, or will it act like two different signals and
interfere with each other?

-Curious