This circuit works on analog I/O ports and was suggested by an Electronic Design from the 90s. It can be used to work as a shield in projects with microcontrollers.
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...