This circuit has more power than the previous one, since it includes a powerful transistorized stage. The circuit is from Radio Electronics from July 1985. It includes the power supply.
In fact, this circuit found in a 1960 transistor manual from Sylvania, simply turns on a lamp when...
This circuit converts pulse frequency to current, which is indicated on an analog instrument. The...
This circuit causes an LED to blink when night falls. Sensitivity is set at R1 and the blinking...