This sequential tone generator circuit was found in the July 1980 issue of Radio Electronics magazine. It uses well-known integrated circuits. The tones are generated by programming resistors.
This circuit is from the manual of the components used, from the 80s. The circuit is valid for...
In the figure we have the way to obtain an adjustable constant current source of 2 mA. The...
This simple circuit is powered by the logic circuit itself. Components are still common, although...