Sensibly equivalent¶ to:
The EM81 is a side viewing tuning indicator. This exhibit is amazing in the fact that the printing on the envelope covers the viewing window.
The Mullard version of the same valve does not obscure its own window.
The thin glass tube envelope is 20 mm in diameter and, excluding the B9A base pins, is 57 mm tall.
References: Data-sheet & 1040. Type EM81 was first introduced in 1956.
Absolute Maximum Operating Conditions¶
Updated November 18, 2013. shape:thin.glass.tube construction:all.glass type:tuning.indicator age:1950.1960 base:b9a heater:6.3v pins:9 pin:1.g1 pin:2.k.g1 pin:3.ic pin:4.h pin:5.h pin:6.ic pin:7.a pin:8.ic pin:9.t