The A2674 is a small valve that came complete with a PTFE base. At first sight the valve appears to be a triode. It took bright sunshine and a magnifying glass to see the ultra fine wire of the control grid as it passed with a minute separation in the front of the 5 mm wide flat cathode. The clue to the presence of the second grid was the obvious presence of the two sets of stout wire grid supports.

The construction is typical of very high gm valves. As the anode is substantial this is probably a valve capable of some power. Putting it together suggests a wide bandwidth valve, probably a video amplifier for instrumentation use. Maybe similar to E55L.

The wide glass tube envelope is 26 mm in diameter and, excluding the B9D base pins, is 39 mm tall.

This exhibit was last updated on 12 March 2006