We found this circuit in the April 1993 Electronics Now magazine. Almost any general-purpose JFET can be used. Power is supplied by a battery (2 x 9V).
The diodes in this circuit are used for waveform correction. The circuit is from Electronics Now...
Found in a Hands On Electronics from the 80's this circuit allows the reading of low resistances in...
This circuit has a gain of 10 for DC signals. The circuit is from a Radio Electronics from May...