The 210VPT is a variable-mu amplifier HF pentode dating from the early 1930s. The design use is as an HF or IF voltage amplifier in AGC controlled battery superhet radio receivers.
In this example the identification is within a paper label and the top cap is of the Bakelite and screw top variety. Thus this dates to the early 1930s. Later 210VPTs had the identification printed onto the zinc paint and the top hat top cap connection.
The rest of the envelope is plain zinc paint coated.
The classic envelope is 44 mm in diameter and, excluding the B7 base pins, is 108 mm tall.
References: Datasheet & 1043. Type 210VPT was first introduced in 1934.
Absolute Maximum Operating Conditions¶
Updated November 20, 2016.