This configuration was found in an English magazine from 1965. It is valid for any junction FET. The input impedance is 5.5 M ohm higher than conventional stages.
We found this circuit in an 80's Radio Electronics. It can still be easily assembled as the used...
This source was found in a 1982 American publication, but can be easily assembled using 2N2995 (PNP...
This ultra-low noise circuit was found in the May 1990 issue of Radio Electronics magazine. The...