The EA52 disc seal UHF diode dates from 1950. The cathode is the annular ring and the anode is the end spike.

This valve was designed for use in UHF voltmeter and monitoring devices. The pointed tip allows it to be used directly as the probe.

See also EA52 for the valve in a probe housing.

The thin glass tube envelope is 11 mm in diameter and, excluding the base pins, is 40 mm tall.

Reference: Datasheet. Type EA52 was first introduced^¶ in 1950.

 
Absolute Maximum Operating Conditions^¶

Diode	Vh	Ah
	6.3	0.3

Thanks to Frank Philipse for supplying the above PDF datasheet

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