Broadband, ignitorless crystal protector tube

A broadband, gaseous crystal protector tube has been developed which is ignitorless and consequently requires no external power source. The conventional microwave crystal protector tube requires an external voltage which is applied to an ignitor electrode for the purpose of maintaining an auxiliary gas discharge as a ready source of electrons. As a result, an electron density of sufficient magnitude appears in the gap of the microwave cavity which aids ionization of the gas at low microwave power levels. Lower ionization power in turn results in less energy at the crystal and prevents crystal burnout.