This 1-transistor circuit for currents up to 50 mA was found in the August 1974 Radio Electronics magazine. The transformer is 50 to 200 mA.
This circuit, from an old Argentine publication, makes it possible to use a 1 mA full-scale...
We found this circuit in a 1997 documentation. It uses a common analog indicator, measuring...
The operational amplifier used in this application obtained in a technical documentation from the...