Used by radio amateurs to accompany telegraphic transmissions, this circuit generates an audio tone. The power comes from the transmitted RF signal itself.
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...