WD11

Work on this tube started at the Westinghouse laboratories in Bloomfield, New Jersey in mid to late 1921. It was designed for use as a detector in the Westinghouse Aeriola Senior radio. This set was announced in the RCA catalog "Radio Enters The Home" published June 22nd, 1922.

Oxide coated, first without getter then lime-getter. First form with a brass base (BB) with tip. Second has bakelite base and is smaller, tipped. Third version is bakelite, no tipp, clear. Then bakelite, no tip but opaque getter (not clear). The last verion of this tube had silvered gettering. Plate has a bigger diameter at the base. It was made by a few of the major manufacturers in the US, Mullard in England (M.D.3A)and Philips in Holland listed the base as available. It is not known what type number was used for the Philips tube. .