One of the best buys I've ever made is this transmitter antenna switch box. This MFJ-4726 switch allows you to operate up to 6 radios and 6 antennas without having to change any coax jumpers. It is an electronically switching setup. It operates on 12 volts from my power supply. If you have more than one radio and or antenna, it will allow you to change from one radio to any selection of antenna you have at the flip of a switch. I currently have 5 radios and soon to be 6 along with 3 different antennas and one 1500 watt dummy load that I use this unit with.