This receiver uses old transistors that are equivalent to BC548 and BC558. The photo diode is of any type. The receiver can be used on a highly sensitive audio link.
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...