This step of good gain was obtained in an American publication of the 1980s. The circuit can be powered by voltages from 3 to 9 V and the FET can be of almost any type.
This circuit is from an English magazine of 1974, but can still be assembled with the replacement of...
This circuit, using a unijunction transistor (UJT), converts a voltage applied to the input in a...
This circuit was found in documentation from the 80s. The circuit did not include resistors from...