This amplifier for electrometer can work with currents of 0.1 pA in a band of 1 Hz. The circuit is from NASA in a publication of the 60s. Transistors are general purpose types.
Other series amplifiers such as the MC3301, MC3401 and LM2900 can be used on this circuit. We...
This circuit was found in a 1980s English publication, but can still be easily assembled by the...
Originally suggested by Electronic Design in a 1965 documentation for use with oscilloscopes, this probe has...