Mercury vapour rectifiers of the GU1 class were introduced in the mid-1930s but, despite filling a real need, they became unpopular because they were troublesome in service.

It took valve designers an amazingly long time to learn that the oxide-coated filament had to be shielded from the anode, that the anode-shield gap needed to be uniform and smoothly profiled, and that use of a thermal delay switch (e.g. DLS10) was essential. The RG1-240A is a later rectifier exemplifying these features. It was successful and widely used. Exhibit NU8 (equal to RG1-125) exemplifies an earlier, much less successful design which the Navy nevertheless went on using for years.

The RG1-240A is a high voltage half wave rectifier. To deliver DC power to medium sized equipment, several would be operated together. Maybe six on a three phase supply.

The maximum reservoir capacitor had to be limited to 5 µF.

The classic envelope is 44 mm in diameter and, excluding the B4 base pins, is 117 mm tall.

 
Pin Connections

B4	1	2	3	4
	-	-	f	f

 
Absolute Maximum Operating Conditions

Rectifier	Vh	Ah	Va	mAa
	4.0	2.7	2,220	250

This exhibit was last updated on 31 January 2004