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 VHF transmitter was found in Radio Electronics magazine from June 1964. The transistor is an...
This two-transistor circuit is from a Radio Electronics magazine from April 1965. The transistors are...
This circuit was found in a 1967 documentation. The switch diode is a component of the time and is...