We found this circuit in the May 1989 Radio Electronics magazine. The circuit can have its values changed to operate at other frequencies and the power supply must be symmetrical.
This SCS counter circuit was found in a 1964 General Electric documentation. The circuit has a...
This simple 1-transistor reflex receiver was published in Radio Electronics magazine in September 1959....
Operational amplifiers used in this 80's circuit is not very common today, but the setting can be...