The 5642 is an EHT rectifier diode designed specifically for use in oscilloscope EHT supplies and as a measuring instrument component it is a special quality device, the naming convention clearly shows this.
The consumer DY70 is closely related to this special quality professional device.
The filament is a close wound helix and is oxide coated.
The thin glass tube envelope is 9 mm in diameter, and excluding the lead out wires is 48 mm tall.
Reference: Datasheet. Type 5642 was first introduced in 1953.
Absolute Maximum Operating Conditions¶
Updated February 25, 2017. shape:thin.glass.tube construction:all.glass type:rectifier.hw age:1950.1960 base: pin: