This FM micro transmitter was found in an 80s spy book. The circuit can work with equivalent FETs and is powered by a voltage of 0.6 to 6 V. Details of the coil are given next to the diagram.
This simple SCR delay circuit for activating a relay was found in documentation from the 1980s. The...
This circuit was found in a 73 magazine for radio amateurs of the 90s. The circuit uses two types...
This FM detector circuit was found in a 1977 documentation. The circuit uses a 1977 Signetics...