This audio circuit was published in a Rado Electronics issue from October 1963. The transistors are from the time and the output is low impedance. Power is supplied with a voltage of 12 V.
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...