A Dorrough 310 is way more than enough for processing just your voice for hamateur use, so nothing else except a mic pre-amp (to bring your mic up to line level) would be needed. The unit was designed to drive broadcast transmitters back in the days when they took a lot of level to reach full modulation and had headroom to spare. The isolation, typically an "H" pad, is used when feeding an inductive load such as a transmitter with a transformer input. Depending on your transmitter, you might need to attenuate the output considerably, particularly for microphone level inputs. Having a manual for the 310 is a must because there are several critical settings such as the FET bias for each band. There are also low-noise substitutes for the original 741 op-amps that would be worth installing.