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.
In the figure we have the typical configuration of a voltage regulator based on an operational amplifier....
This circuit makes use of a 741 single source operational amplifier to measure resistors on a...
Active with the output at the high level, this oscillator was found in November 1984 Radio...