199_experimental

This is a very early experimental version of the (UV)199 using a double ended baseless design. Work on the development of the tube started  at the GE laboratories early in 1921 and in June and July of that year, samples were supplied to the Radio Dept of GE for consideration in connection with the future design of receiving sets.  There is an extra lead bought out  in this tube that is not needed. The plate in this tube is considerably larger than that used in the final version (see 199_prototype). The exhaust tip is bent over at a right angle, perhaps to lessen the chance of breakage. The five lead-in wires are approximately 15 mm long. The paper label on the tube simply says 2.  These tubes are not listed in Tyne's "Saga of thee Vacuum Tube" . In May 1922 the design was changed to a single ended tube.