Sensibly equivalent¶ to:
The U149 full wave rectifier is almost identical to the American Type 7Y4.
By the time this specimen was made the Marconiphone brand had only loose connections with M-OV and purchased their valves from numerous suppliers. This exhibit does not look like an M-OV product.
The maximum reservoir capacitor is 40 µF and the minimum series resistance, for current limiting, is not given in the literature.
The cathode can be seen as a white tube in the centre of the picture. The anodes are mainly fins for heat dissipation.
The wide glass tube envelope is 28 mm in diameter and, excluding the B8B base pins, is 55 mm tall.
References: Datasheet & 1040. Type U149 was first introduced in 1950.
Absolute Maximum Operating Conditions¶
Updated December03, 2012.