This circuit can work with almost any JFET. The circuit is from an Electronics Now from April 1993. It is powered by a 12 V battery, but can also be powered by 9 V.
This circuit is from an English magazine of 1977. The circuit is still current, just using BC547...
This circuit was obtained in an old Elektor. It is a reference, since the integrated products of the...
This circuit was found in a European technical documentation from 1991. It is a circuit that must...