Found in a Hands-On Electronics from the 90s, this circuit produces the dial tones of an old telephone. The integrated circuit used is uncommon today.
This circuit was obtained in a 90’s Popular Electronics. The frequency depends on C1, a component...
This short-range circuit can act as a wireless microphone. We got the schematic and the printed...
This sophisticated function generator circuit appeared in the September 1972 issue of Radio...