The EY51 is a high voltage rectifier for use in television and similar EHT circuits. The cathode is cylindrical and placed within the bell of the anode cavity.
The valve is designed for pulsed operation. The anode PIV is 17 kV and the rectified current has a maximum average value of 350 µA and a peak value of 80 mA. The reservoir capacitor can take a maximum value of 5,000 pF.
The anode support is secured into the top of the glass. The evacuation tube is at the cathode end.
The heater/cathode is placed at the centre of the anode.
The thin glass tube envelope is 14 mm in diameter and, excluding the base wires is 51 mm tip to tip.
References: Data-sheet & 1040. Type EY51 was first introduced in 1948. See also1948 adverts.