This test instrument was found in the April 1991 issue of Radio Electronics magazine. The circuit has good signal strength.
Other operational amplifiers of the same the series, such as the MC34072, MC34074, MC35071,...
September 2017 - Würth Elektronik High Power Ultraviolet LEDs can be obtained from Mouser...
How about a rhythmic light system that uses only one component? If you think this is impossible, it’s...