This sequential tone generator circuit was found in the July 1980 issue of Radio Electronics magazine. It uses well-known integrated circuits. The tones are generated by programming resistors.
We found this circuit in a documentation for radio amateurs from 1977. The circuit can be changed to...
This is the complete circuit of a binary counter for educational purposes. Found in the February 1973...
This old circuit that makes use of germanium transistors, can be modernized with the use of...