This mixer with 20 dB gain per channel uses RCA's CA3048 integrated circuits. We found it in the July 1971 Radio Electronics magazine. The power supply does not need to be symmetrical.
With this circuit, a relay can be activated from an alternating signal with frequency up to a few...
With this circuit the visually impaired can easily locate important places inside the house, such...
In the figure we have the way to use the transistors of an old-paired pair as a trigger circuit. The...