This optically coupled circuit was found in the February 1968 Radio Electronics magazine. The circuit uses an LDR in modulation. Transistors are types of the time.
This light comparator is of the window type already explored on this website in several...
Using the integrated circuit DCP01051D this circuit was found in the magazine Electronics Now of...
This filter with the operational 741 passes the frequency range between 300 Hz and 3,400 Hz. This...