Found in an Electronics Now from the 1980s, this circuit uses some components that are still common today. For others, equivalents can be tested.
We found this circuit with JFETs in a Radio Electronics magazine from June 1969. The circuit has...
Indicated for frequency measurements, this circuit can operate with inputs up to 1 MHz. We found...
This general-purpose transistor audio amplifier was found in the March 1990 issue of Radio...