This circuit is from an 80's Radio Electronics. The circuit has several output options for 50 mA currents with load indicator through LEDs.
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...