An L-band crossed-field amplifier chain

A pulsed L-band amplifier chain consisting of two crossed-field amplifiers operating in tandem will be described. The final tube of the chain gives an output of about megawatt peak with an input of 100 kw peak. The driver tube gives an output of over 100 kw peak with an input of about 1 kilowatt peak. The duty cycle is .002 and bandwidth is 10%. Both of these tubes are representatives of a new dass of crossed-field amplifier which utilize forward wave interaction and a re-entrant electron stream. A forward wave circuit is obtained by a novel means of alternate capacitive coupling of half-wave length bars. Coaxial input and output lines are used to couple to the first and last bars of the circuit.