Sensibly equivalent¶ to:
The Tungsram HR210 is a battery triode and is equivalent to the Mullard PM1HL etc. These very popular valves were used as detectors.
HR210 has a balloon envelope and HR210 has the classic shape but no metallic paint..
The classic envelope is 40 mm in diameter, and excluding the B4 base pins is 84 mm tall.
References: Data-sheet & 1043. Type HR210 was first introduced in 1933.
Absolute Maximum Operating Conditions¶
PDF scanned from an original document held by the museum
Updated February 09, 2013. shape:classic construction:pinch type:triode age:1930.1940 base:b4 heater:2.0v pins:4 pin:1.a pin:2.g1 pin:3.f pin:4.f