The U147 is a full wave HT rectifier for low power AC mains driven equipment. The anodes are placed either side of the cathode which allows the height to be over 15 mm shorter than the Marconi U147 version.
There is little information about the U147.
A effective series resistance of 350 Ohms was required to limit surges and the reservoir capacitor had to be restricted to 16 µF.
The anode plates are offset and each connects to one support with an additional tab inserted into the mica to ensure the plate does not move.
This rectifier has failed by the heater burning out. The right hand heater wire is missing a length suggesting that this was connected to too high a heater voltage.
The wide glass tube envelope is 29 mm in diameter and excluding the IO base pins the valve is 61 mm tall.
Reference: 3002. Type U147 was first introduced in 1950. See also1950 adverts.
