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.
Found in American documentation from the 1970s, this circuit employs an integrated circuit from...
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...
This assembly circuit using a small motor as a generator was found in Radio Electroics magazine from...