Found in an Analog Devices documentation from the 90s, this circuit uses operational amplifiers from the time. The power supply must be symmetrical.
This circuit is suitable for use in radio receivers to improve the quality of weak signal...
This power source was found in a Motorola manual from 1968. Transistors are from the era, and...
This circuit should be placed between a turntable and recorder or playback media from the input to...