This circuit is an improvement over the previous one, using the same capacitor system as a sensor. We also found it in Radio Electronics from the 80s.
The first circuit is shown in figure 3 and uses a 2N2222 transistor or equivalent. This circuit can...
This half-wave regenerative control was found in an old RCA manual. The circuit can be designed...
In the figure we have the way to use a common operational amplifier for AC signals. The resistor...