If you have the skills and can get your hands on SMD components, you can assemble this small amplifier. We found it in the Radio Electronics Experimenter special edition from 1990.
An integrated circuit 741 (operational amplifier is the basis of this voltage indicator, which can also...
This circuit converts inductances on two scales into voltages. The circuit was obtained from a...
This field effect transistor amplifier circuit in common gate or common port configuration is from an old...