We found this circuit in the November 1995 Electronics Now magazine. The circuit is more accurate than the previous one using an external multimeter as an indicator.
This Vox or sound activated relay was found in an American documentation from 1975. Equivalent...
This circuit is from Motorola's Linear Interface ICs from 1993. The circuit uses a booster...
The existence of field effect transistors at the input of the integrated circuit (operational...