We found this circuit in an old publication. The components used are rare today. Accuracy depends on the resistors in the input selection network. The circuit operates from 10 to 500 kHz.
A touch of the sensor makes the load bistable (load) connected in Q1. For a BC548, a 6 V or 12 V...
With the use of an additional diode and a resistor, the configuration of the figure can be...
This circuit was found in documentation from the 1980s. The circuit uses several components of the...