The 117Z3 is an American half wave rectifier valve. It uses the USA mains voltage as both the heater supply and the anode voltage. It will produce DC for low cost applications.
Side view of the anode: the plates have been opened out for greater radiating area.
Face view showing the stitches holding the two halves of the anode together. On the glass is the Sylvania name.
The thin glass tube envelope is 18 mm in diameter and, excluding the B7G base pins, is 57 mm tall.
Reference: Data-sheet. Type 117Z3 was first introduced in 1948. See also1948 adverts.
