Development of a metal anode ignitron switch tube

A study has been made of a refractory metal-anode mercury-pool switch tube for transferring energy from capacitor banks to experimental apparatus for producing electron-ion plasma, pulsed magnetic fields and other applications. One of the special-purpose applications for these tubes is transferring stored energy from capacitor banks to experimental thermonuclear-fusion devices. In this application the tube must hold off 104 to 105 volts, carry peak currents of the order of 104 to 106 amperes, and have low inductance to allow for fast current rise. Since many of the L-C (inductance capacitance) circuits are not critically damped, the anode of the tube becomes alternately a cathode. The use of tubes in these circuits presents a new duty cycle for ignitrons, and often the conventional ignitron fails to have adequate life of several thousand operations.