Variable gain operational amplifier (CB8068E)

This circuit is from an Electronics Now from the 90s. It applies to almost any operational amplifier. See formulas for component calculation.

| Clique na imagem para ampliar |

Fan Control II (CB12745E)
What differentiates the circuit shown in the figure is the use of two inverter gates to trigger the...
Discharge Limiter (CB4983E)
The purpose of this circuit is to turn off the power supplied by a battery when its voltage drops...
Super Regenerative FM Receiver (CB16955E)
We found this conventional receiver circuit in a 1990 documentation. The circuit includes an audio...