The PA222 integrated circuit used in this project from an American 1967 documentation is not common today. The circuit can deliver higher power with lower fidelity.
This circuit was obtained from a Hands-On Electronics, an American magazine from January 1987. The...
This receiver for listening to the TR-23 phone was manufactured in Japan in the 1960s. The circuit is...
This astable multivibrator with an operational one at the time was found in the National...