Development and production of a DBS band, 1,250 watt peak power Superlinear® helix TWT

Communications and Power Industries (CPI) has designed and manufactured the VTU-6398D9C, a compact high peak power, high linear power, high efficiency, and conduction-cooled helix vacuum electron device. The helix traveling wave tube operates with a 1,100 MHz instantaneous bandwidth and covers the full extended DBS band of 17.3 to 18.4 GHz. The minimum peak rf output power is 1,250 watts, and the typical CW-rated linear output power is 625 watts. The small signal gain is typically 49 dB, and the total gain variation over the full extended band is typically less than 1.5 dB. High overall efficiency is obtained by using a robust two-stage depressed collector and selecting operating voltages that simultaneously increase efficiency, reduce prime power, and maintain low body/helix current. Prime power is typically 2,250 watts. The TWT has overall dimensions of 4 inches wide by 16 inches long and weighs 9.7 pounds. The predicted and measured performance data are compared.