This circuit is the digital indicator for the previous circuit and can be used with similar circuits. The circuit is from an article in Radio Electronics magazine, June 1987.
With this circuit, a relay can be activated from an alternating signal with frequency up to a few...
With this circuit the visually impaired can easily locate important places inside the house, such...
In the figure we have the way to use the transistors of an old-paired pair as a trigger circuit. The...