This circuit is from a 1990s publication by William Sheets. The circuit consists of a stage whose gain is adjusted according to the signal intensity.
In the figure we have a typical polarization circuit for MOSFETs with a high impedance...
Equivalent transistors, like the BC548 and BC558 pair can be used in this circuit that we find in an...
The circuit presented is from an old magazine having been translated and published in a national...