Found in a 90s R-E Experimenter Handbook, this circuit has a greater gain than the previous one for presenting two stages. The integrated circuit used is uncommon today.
Using an operational amplifier with FET, this voltmeter has a high input resistance. The circuit has...
This circuit is from 1998 documentation. The coils consist of the number of turns indicated on...
We found this oscillator in a documentation for radio amateurs from the 1970s. The circuit can use...