Oxide indirect cathode. Feed Through Capacitance: <0.003pF. The date of manufacture is 1975. Output Capacitance: 7.0 ± 1.8pF. Input Capacitance: 6.0 ± 1.2pF. Leakage current cathode-heater: <20 μA. The steepness at the beginning of the characteristic (Uc1 = -35V): 1.
