This amplifier for instrumentation with very high input impedance was found in a manual of JFET circuits. The operational ones used are current and the power supply must be symmetrical.
The frequency of this oscillator depends on the crystal used and the transistors. The circuit was...
This circuit shows how to use the 4007 MOSFETs in an amplifier stage. We found it in an...
This circuit was found in a 1967 Japanese documentation. It consists of a touch control system with...