Triode RD50XM

Air-cooled triode for frequencies up to 30 MHz, 17 V / 150 A heater, maximal anode voltage 20 kV, 50 kW anode power. These air-cooled tubes were used as modulator and high-frequency output stages in the Blaw-Knox transmitter in Liblice, which operated between 1958 and 1972. More modern transmitters of such power used water cooling.