This circuit is from Radio Electronics from March 1977. The integrated circuit is from that time and the circuit is intended for an infrared audio link. The modulation is in pulse frequency.
This circuit activates a water pump when the sensors detect lack of humidity in a vessel, for...
This circuit was obtained from an Electronics World of 1969. General-purpose transistors can be...
This circuit was found in many record players with crystal phono pickups. The output power is 800...