This amplifier with fixed AC bias was found in a 1947 documentation. The circuit uses two transformers in the power supply and two full-wave rectifier tubes.
This circuit can serve as a basis for a digital mixer or simply for a noiseless switch of audio...
This traditional mixer configuration with a high input impedance was found in a 90’s Popular...
This medium wave radio works with any general purpose NPN transistor. The diode must be made of...