High peak power tubes and gate effect klystrons

By carefully extending the technology, the peak power of the klystrons can be higher than the usual 50 to 60 MW. Moreover, thanks to the present development of the pulse compressors, peak power is also increased toward the range of 200 to 300 MW. The gate effect klystron seems to be one of the best candidate for GW pulses. These tubes use low impedance - 20 to 100 Ω - intense annular electron beams. They are compact not only because of reduced high voltages but also because the cavities are few in number and the drift tubes almost non existent. These very high power tubes (>; GW) are amplifiers and not oscillators like their competitors, the relativistic magnetrons or the vircators.