Using the 741 this basic circuit was found in the November 1973 Radio Electronics magazine. The power supply must be symmetrical. The components can be recalculated for other frequencies.
We found this circuit in a Popular Electronics from the 80s. The circuit is based on the LM3909, a low...
In the figure we have the basic configuration of an operational amplifier for AC signals using the...
This timer, like the previous circuits, uses a currently uncommon integrated circuit. The time is...