This circuit was found in a 1965 Electronic Design. The transistors are of the time, but the circuit applies to modern equivalent transistors.
This preamplifier for record players with crystal capsules was found in Radio Electronics magazine...
Modern operations can be used in this circuit that multiplies a capacitance of 10,000 uF for a...
This interesting circuit, found in a 1997 documentation, allows you to view the characteristic curves of...