Designed to operate with a video camera, this small transmitter was found in the February 1993 issue of Radio Electronics magazine. The microphone is electret.
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...