Found in American documentation from the 90's, this JFET stage has an input impedance of 500 M ohms. Bipolar transistors are general purpose types and the FET supports an equivalent.
We find this circuit in a 1980s documentation. The circuit uses uncommon components today which can...
We found this circuit in a 1977 Radio Shack documentation. The circuit should be powered, for...
With the circuit shown in the figure it is possible to digitally control the gain of an...