This high quality circuit with complementary symmetry was found in an Electronics World of 1966. It can be made with modern transistors like the BD or TIP series.
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...