The UR2 is a rectifier with a mesh anode and dates from 1934-5. The Universal range of valves were designed to have their heaters run in a chain across the incoming mains with a Barretter to stabilise the current. The UR2 was specified for use as a full wave rectifier, a half wave rectifier with both halves in parallel or as a voltage doubler. The heater cathode insulation was substantial to allow for the stresses of a large heater cathode voltage differential.
The lettering is at the top of the envelope and provides basic operating details.
The classic envelope is 40 mm in diameter, and excluding the Ct8 base pins, is 95 mm tall.
References: Datasheet & 1043. Type UR2 was first introduced in 1934.
Absolute Maximum Operating Conditions¶
PDF scanned from an original document held by the museum
Updated December31, 2012. shape:classic construction:pinch type:rectifier.fw age:1930.1940 base:ct8 heater:200ma pins:8 pin:1.k(1) pin:2.h pin:3.h pin:4.k(2) pin:5.a(1) pin:6.- pin:7.- pin:8.a(2)