This circuit was obtained from a 1977 FET manual. The circuit measures inductances using a signal generator as a reference. The range is from 60 uH to 60 000 H. The FET can be a BF245.
This series LED circuit was found in the February 1992 issue of Radio Electronics magazine. The...
We found this circuit in the Linear Applications Handbook by National Semiconductor. The circuit uses...
The noise comes from the PN junction of a common silicon diode. Since no gain is given by the...