This circuit includes the power supply from the power grid. We found it in Radio Electronics from July 1985. It can still be assembled easily today.
This simple photometer circuit uses an LDR as a sensor and the indicator is a sensitive...
This circuit with SCR was found in an old documentation. The SCR can be the TIC106, and the...
Found in an old publication, this circuit uses an analog milliammeter to indicate the position of a...