U20aS, power supply for the 20W.S.b transmitter
 
 
 
Exterior of the umformer.

 

 

The data plate. No year of manufacture is stated.

 

 

Inside the top cover.

 

 

Schematic. Standard umformer schematic with motor/generator, filters and an activation relay triggered by 12 volts going to the central pin of the power connector.

 

 

Internal components.

 

 

Filter capacitors and inductors.

 

 

Two filter chokes are shielded by these aluminum caps.

 

 

Motor/generator.

 

 

Another photo of the motor/generator.

 

 

Interesting non-standard box-capacitors. Was this umformer manufactured in the Czech republic?

 

 

Bundled filter capacitors.

 

 
 

 

 

 
 

 

 

 
 
 

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