Suitable for clandestine listening and in SMD assembly, this circuit was found in the Radio Eletronics magazine of August 1988. The listening is in headphones and the amplifier is electret.
As in the previous case (CB5045E), we have in the circuit of the figure the use of the polarized...
This switch can only be triggered when the mains voltage goes through zero and can operate as a...
This circuit was found in the January 1992 issue of Radio Electronics magazine. The capacitor...