The VT-127A is a power triode of 100 Watt dissipation. The valve is directly heated with an oxide coated helical filament. The grid is a wire cage with a helical wire around it. The VHF construction has the Anode brought out to connections either side of the bulb. The grid is similarly brought out to a pair of connections. All connecting pins pass through Uranium glass seals.
The VT-127A was designed to operate as a ring oscillator at 205 MHz. The American SCR-268 radar, for the control of anti-aircraft guns, used 16 of this type of valve for the power oscillator. Operated in pulse mode the total power output was of the order of 60 kW.
