This circuit is designed to measure very weak currents, in the order of picoamperes. We found it in an American documentation from the 80s. The integrated circuit is from that time.
We found this circuit very simple in an old documentation. The relay is high voltage sensitive, but...
This circuit was found in an Elektor from the 90s. The circuit uses common components even today,...
The circuit, shown in figure 2, is a monostable multivibrator with two NAND ports out of the 4...