Nanosecond risetime avalanche transistor circuit for triggering a nitrogen laser

Using avalanche transistors, a trigger unit capable of producing several kilovolts in 25 nanoseconds—total risetime—has been constructed. We have used such a circuit to drive a nitrogen laser, resulting in a substantial decrement of the delay time between trigger signal input and the attainment of lasing which is common in commercial lasers. The minimum delay obtained is only limited by the switching time of the thyratron employed. In addition, the ±2 ns jitter of the commercial laser has been reduced to ±0.4 ns using the circuits here described. In order to effect a high degree of reliability, special attention was given to ’’burn-in’’ and selection of the avalanche transistors.