A radio power output amplifier comprises a balanced radio power output that differentially
drives a dipole antenna or other balanced load. One half of the differential power
output drives one side of the antenna from ground to the maximum positive rail,
while the other half of the differential power output drives the opposite side
of the antenna from the maximum positive rail to ground. The result is a voltage
swing across the antenna that is twice that which would occur if a single ended
output was driving an unbalanced load. Since the power output is the square of
the voltage divided by the load impedance, the result is four times the power output.