This circuit can detect static charges or extremely low voltages. The circuit was found in ancient American documentation and makes use of a JFET. A BF245 which is a more modern transistor can be used.
The configuration shown can be applied to modern operational amplifierso with common power...
This circuit appeared in Radio Elecronics magazine in 1968. The operating circuit is a...
The circuit shown is from a September 1973 Radio Electronics. It reduces the full scale of a...