This IR light sensor circuit was found in the July 1992 issue of Radio Electronics magazine. It is tuned for 20 kHz modulated light.
This old configuration of an audio amplifier has a push-pull two-transistor output stage. Output...
This is the traditional configuration of na Astable Multivibrator using two NPN ttransistor....
This circuit is from 1987 documentation. The operating system used is not common today, but two...