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.
Using an operational amplifier, this circuit was found in the March 1996 issue of Electronics Now...
This simple transistor gain test acts as an oscillator for the transistor under test. The circuit is...
Found in a 1980 documentation, this circuit drives a transducer (X1) when the car battery has its...