We have a stock of scarce new boxed stock of the U19 HW rectifier by Osram.
The U19 is a high voltage half-wave rectifier with an intrinsic series resistance of 600 Ohms and a maximum capacitance rating of 4uF. The anode is carbonised to aid dissipation of heat generated and the whole electrode structure smacks of longevity and supreme build quality having been anchored with ceramic supports and insulators. It presents on a vast scale too being approx 166 mm in height. Osram introduced this valve type for Air Ministry useage in 1947.