... thoriated tungstenHeating direct, DC or single phase ACFilament voltage 4.2 V (1)Filament current 125A (1)Interelectrode capacitances, approx,: ... factor, average 8Operating position verticalWeight, approx. 7kg Anode cooling (2) forced air Air flow, min. 13000L/min Corresponding pressure drop ... 5 kVScreen-grid voltage 600 600 VAnode current, with signal 2.7 3.25 AAnode current, at zero signal 1. ...