Review of energy saving, gained by the use of the MSDC klystron in a UHF TV transmitter

The UHF TV klystron as first employed in the early 1960´s gained popularity on account of its rugged design and consequent long life. At the time its low efficiency, in the order of 30-35% at peak sync, was largely overlooked. Rising electricity prices in the 1970´s drew attention to the efficiency and resulted in a number of developments aimed at its improvement and a subsequent reduction in its electricity consumption. The latest of these developments is the multi-stage depressed collector (MSDC) klystron. The author describes simply how the MSDC klystron operates. He also outlines the design changes needed in a TV transmitter to accommodate the new tube, and give results of its use in terms of both electricity consumption and performance