This circuit generates signals in four frequency bands with the threshold values indicated in the diagram. The circuit was found in the March 1996 issue of Electronics Now magazine.
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...