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 80's circuit uses a germanium transistor like the AC121. The circuit has an output...
This circuit is from the Motorola Linear Databook of 1990. The circuit controls a Triac from a...
I found this circuit in a Popular Electronics from 1992. The circuit shows how we can receive...