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.
This is the typical circuit of an FET amplifier stage in the common source configuration. The circuit is...
This circuit is interesting for experiments and can be part of the bench in the form of a module. The...
This oscillator can use any CMOS inverter. The circuit is crystal controlled and was found in the...