The figure shows how to couple two TTL circuits using an optical coupler to obtain isolation. The circuit is shown in the August 1992 issue of Radio Electronics magazine.
Found in an English documentation from 1989, this circuit uses components common today. The...
The LED frequency flashes depends on the value of the capacitor tested according to the table. We...
Found in a Popular Electronics from the 90s, this circuit generates a signal that depends on the...