This circuit was found in Mullard's transistor application manual from 1960. More modern transistors can be used. The zener diodes used have the indicated voltages.
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...