Recent developments in extended interaction oscillators (EIOs) have produced low noise mm-wave radar-transmitter-tube oscillators suitable for use in coherent radar systems. This article focuses on the methods of generating power in the frequency range from 30 to 300 GHz and at power levels from 1 kW to 1 W of CW power using a biperiodic ladder slow-wave circuit in the EIO. It also discusses the measurement of the phase noise exhibited by these oscillators. 2 Refs.