Found in the 1976 Siemens transistors manual, this circuit works with AM or FM IF signals. In the diagram information is given for the coils.
The presented circuit was found in a 90’s Electronic Engineering. The circuit is based on CMOS...
We find the original version of this circuit in an English publication (1986). It is a...
Found in a 1990s Electronics Now, this circuit uses a period-specific integrated circuit that...