This is a very useful autotransformer circuit on the bench. We found it in the September 1970 Radio Elecronics magazine. The transformer must be according to what you want to feed at the output.
We found this circuit in an old 1980s documentation. The circuit can be implemented with modern...
This circuit is from a Linear datasheet. The circuit provides a 5 m voltage with 40 mA from an AA...
The components of this filter are calculated using conventional formulas (see mathematics section of...