An amplifier system includes a power divider for dividing an input RF signal into M RF signals of equal power and phase. The system has M low power selectable phase shifters each for phase shifting one of the M RF signals. M high power amplifiers are coupled to respective ones of the phase shifters. The system includes an M.times.N power distribution network having M input ports and N output ports, such as a Butler matrix. The M high power amplifiers are connected to a respective one of the M input ports of the distribution network. The phase of the M phase shifters may be adjusted to obtain a maximum output at the desired output with all the other outputs nulled.