The low-noise amplifier shown uses a rare Raytheon operational amplifier today. The circuit can be implemented with more modern operators and the power source must be symmetrical.
This circuit activates a fan when the temperature exceeds a certain value, sensed by diode Q1. The...
This circuit generates sine low-frequency signals. The frequency depends on the twin-T network....
This circuit has four-time programming keys, according to the table given next to the diagram. The circuit...