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.In this exhibit the identification lettering is printed on the top of the screening can.
The base cover with central spigot and location key.The wide glass tube envelope is 33 mm in diameter and, excluding the B9G base pins, is 62 mm tall.References: Data-sheet & 1040. Type EF50 was first introduced in 1939. See also 1939 adverts. |
