This oscillator uses a small IF transformer taken from an old transistor radio. FET admits equivalents. The circuit can be used to calibrate radios.
To use the instrument for AC measurement, the tips are A and B. For CC use tips A or B for...
The interesting circuit shown in the figure, can have its gain digitally controlled and present two...
This simple MW radio was found in a 1975 publication, but it can be mounted with BC548...