High-power printed circuit traveling wave tubes

The printed circuit TWT is a low cost microwave amplifier specifically designed for applications such as phased-array radars where large numbers of tubes are required. The original successful printed circuit TWT provided 20 watts of power at L-band, and used a single printed meanderline for its microwave interaction circuit. For higher power and higher frequency operation, multiple circuits must be used. A study of the various modes that can exist on a multiple circuit slow-wave structure led to the successful construction of a 1.5 kw peak power printed circuit TWT at S-band. The mode study, the high power S-band tube, and a 100 watt peak power X-band multiple circuit tube will be discussed in the paper.