A new L-band, high gain TWT for high performance aircraft requirements

A traveling-wave tube which can meet rigid specifications with regard to performance and durability at high ambient temperatures has been developed. Designed for L band, this tube (the STL-70) is of all metal and ceramic construction with an extremely rigid gun structure capable of being processed at temperatures exceeding 600°C. This tube has a novel input and output match which gives insurance against helix to ground shorts and maintains a vswr of better than 2 to 1 over this band. The small signal gain is approximately 60 db with saturation power exceeding 1 watt. A gridded electron gun with a very high µ is capable of cutting the beam off at a negative bias of 2 or 3 volts. Focused in an aluminum foil magnet this entire package, tube and magnet, weighs approximately 10 pounds. The tube diameter is small enough to accommodate periodic permanent magnetic focusing if desired.