WX-4073

Westinghouse made 4 "matchbox" developmental type tubes. They were numbered with WX and were the -3506, -3608, -3683 and -4073. This was sometime in the late 1950's.

They were designed to be soldered directly to a PCB (circuit board). There was a high failure rate of the fritted seal between the glass and metal, and they never went into production.

They were quickly superceded by the Nuvistor, and then the transistor in the 1960's.

This WX-4073 was a prototype, in a smaller package than the previous 3 in the series. 2 leads out each side.