Found in documentation from the 1980s, this circuit uses a SG1524. It is an uncommon integrated circuit nowadays. The circuit provides a current of 20 mA with a symmetrical voltage between 15 and 18 V.
The operational amplifier for this circuit found in a 1979 documentation may be the 741. We can...
The UM3562 integrated circuit (not very easy to find) synthesizes three types of sound that...
This stethoscope or amplifier for hearing aid using a crystal headset and microphone was found in a...