Although it uses a dual-channel FET, which is hard to find today, this circuit was released in a Radio Electronics issue in April 1986. It serves as a signal booster for a wide range of frequencies.
This circuit was found in a 1977 Radio Shack documentation. The unijunction transistor can be...
Other series amplifiers such as the MC3301, MC3401 and LM2900 can be used on this circuit. We...
This circuit offers excellent sound quality for headphones of 150 ohms or more. The circuit was...