The EF50 was the ubiquitous red valve for a decade. Designed by Philips in 1938 for Band I television receiver use and first released in 1939, this amplifier pentode was a general workhorse. It was extensively used in radio and radar during WWII. One additional reason that so many existed was that they had a short life and so were changed often.This exhibit carries the Pentone trade mark and the letters MSG. As yet we have not found what MSG refers to.
The aluminium base cover and spigot with key. Here all the glass around the pins is all the same shape. In other versions one pin surround is shaped to denote the orientation for the base cover.The wide glass tube envelope is 33 mm in diameter and, excluding the B9G base pins, is 61 mm tall.References: Data-sheet & 1040. Type EF50 was first introduced in 1939. See also 1939 adverts. |
