Rectifier No. 33A & 33B
The Rectifier No. 33A is used with Power Unit TL2529 and the Rectifier No. 33B is used with Battery-Unit N634.  Rectifier No. 33B has a moveable link that can change the charge current rate - see N633.

The rectifier is connected to the Battery-Unit N634 with Cable I.R.V, Core T 1 pair /40.

Rectifier No. 33B
Input: 100//240V, 50 c/s.
Output: 30/50V, 0.025/0.2 amp, D.C.

Introduced circa 1936.

Rectifier No. 33A includes:-
2 x Cut-out No. 121B.
2 x Fuse No. 1/1.
1 x Transformer No. 93A.
3 x Condenser, M.C., No. 103.
1 x Mounting No. 151/1A.
2 x Rectifier-element No. 1/12A.
1 x Coil, Retard No. 40B.
1 x Switch, Tumbler No. 9.

Drawings - 60972 (No. 33A Mark 1) & 63866 (No. 33B Mark 1).

Diagram - TL2529 (No. 33A) & N633 (No. 33B).

Specification - D1762.

Click here for E.I. Power, General S3201 - Installation details (No. 33A).

Click here for E.I. Power, General S3211 - Installation details (No. 33B).
 

Rectifier No. 33A

 

Rectifier No. 33B

 

 
 
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Last revised: January 18, 2026

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