The E92CC double triode is a special quality valve and was designed for use in digital circuits such as flip-flops and counter tube drivers.
IBM built the computers as as a huge business had the valves branded and would sell replacements - lucrative with a valve computer.
The data sheet makes clear that the E92CC will maintain its emission for a long service life even after prolonged periods at cut-off, but that this valve should not be used in circuits that are critical in respect to hum, noise or microphony performance.
Face view of one triode. The control grid is wound on copper rods and there are small heat radiating fins at the top of the supports.
The real maker was Dario (part of Philips at this time) and imported from Holland.
The thin glass tube envelope is 17 mm in diameter and, excluding the B7G base pins, is 59 mm tall.
Reference: Data-sheet. Type E92CC was first introduced in 1958. See also1958 adverts.
