This circuit is from an American documentation from the 90s. The transistors are of power and must be equipped with good heat sinks as well as the integrated voltage regulator.
This mono circuit for 10 LEDs was found in the January 1991 Radio Electronics magazine. It is...
In the figure we have a line receiver circuit (twisted pair) with the possibility of...
This circuit was originally designed for the practice of Morse code, something common in 1966, the year...