This circuit was obtained in a French documentation from 1981 and can be easily assembled. The analog instrument itself can be replaced by the current scale of an ordinary multimeter.
This high impedance and low capacitance buffer employs a junction FET that can be BF245 or...
Found in 1980s documentation, this amplifier uses a symmetric source and the gain is given by the...
This circuit was found in an old documentation for radio amateurs, being indicated for...