Topic summary
Carcinotron
Extracted from the Wikipedia article Backward-wave oscillator.
Carcinotron
The device was originally given the name "carcinotron", after the Greek name for the crayfish, which swim backwards. By simply changing the supply voltage, the device could produce any required frequency across a band that was much larger than any existing microwave amplifier could match - the cavity magnetron worked at a single frequency defined by the physical dimensions of their resonators, and while the klystron amplified an external signal, it only did so efficiently within a small range of frequencies.