Found in a 1960s documentation, this circuit uses an operational amplifier from the time and a current diode, both of which are difficult to find today.
Bipolar transistors are types of general use like BC548, while the power MOSFET can be of any type...
We found this circuit in an old documentation. Its purpose is to turn on warning lights when the...
This simple humidity alarm circuit includes a timed warning oscillator whose time is set to R4....