Brazed-helix technology for 30 GHz power TWTs

Thomson-CSF is developing a new class of brazed-helix traveling wave tubes covering the range of frequencies from 27.5 to 30 GHz. Delay lines employ a specific brazed-helix technology developed by Thomson-CSF over the past few years ensuring good thermal evacuation. RF transmitted power was about 500 watts at 30 GHz on those lines. An original RF coupling has been studied and perfected in order to obtain good matching conditions. Experiments using beam sticks have demonstrated a beam transmission better than 99 %. Several TWTs have been tested and an output power of 100 watts has been obtained. Specific test results will be presented.