Found in a 90s Elektor, this circuit is based on a Maxim integrated circuit of the time. The circuit supplies 5 V at its output with a maximum current of 50 mA.
This circuit simulates an inductor. Or operational amplifier of old type, but a configuration is...
We found this circuit in a 1967 Electronic Design. The circuit uses contemporary transistors that...
To control relays safely with double insulation, we suggest the circuit in the figure. The optical...