The EY88 is an efficiency diode for television line scan service. This is normally found as the PY88 with a 300 mA heater for chain use. The EY88 would be powered by an winding on the line output transformer.
The peak voltage can reach 6,000 Volts and the peak current can rise safely to 550 mA.
This exhibit carries the older Mullard logo but was an imported valve.
With the cathode at the top cap and the high inverse voltages the heater is kept away from the sides of the cathode by two supports with a fine wire wound round them. This can be seen near the base as a grid-like structure.
The inner surface of the anode is left bright. To accommodate the side flanges they are turned out revealing the inside of the anode.
The thin glass tube envelope is 20 mm in diameter and, excluding the B9A base pins, is 79 mm tall.
Reference: Data-sheet. Type EY88 was first introduced in 1959. See also1959 adverts.
