The U319 is a half wave rectifier designed for 300 mA heater chain equipment. It is therefore probable that VHF TV receivers would be the natural home of this valve. The effective series resistance required by the U319 is 55 Ω.
The stitched anode with the round cathode tube visible near the mica discs.
The insulated heater passes several times through the cathode tube. At the top of the cathode the heater looks to be covered in more insulation that spills over onto the cathode tube.
The thin glass tube envelope is 21 mm in diameter and, excluding the B9A base pins, is 68 mm tall.
Reference: Data-sheet. Type U319 was first introduced in 1953. See also1953 adverts.
