This circuit is from an ancient American documentation. The integrated circuit is 741 and the power supply must be symmetrical. The passing band is centered at 1 kHz.
The great advantage of the circuit shown in the figure is that its frequency is controlled by a...
This circuit for a receiver was found in an English documentation from 1963. The transistor is made of...
This circuit was obtained from a Linear Technology manual from the 1990s. The components may have...