The U149 is basically identical to the American Type 7Y4. By the time this specimen was made the Marconiphone brand had only loose connections with MOV and purchased their valves from numerous suppliers. This exhibit does not look like an MOV product.

The U149 is a full wave rectifier.

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.

 
Pin Connections

B8B	1	2	3	4	5	6	7	8
	h	-	a(2)	-	-	a(1)	k	h

 
Absolute Maximum Operating Conditions

Rectifier	Vh	Ah	Va	mAa
	6.3	0.5	325	70

This exhibit was last updated on 31 January 2004