This high-impedance headphone circuit was found in a 1990s William Sheets. The power is low, but the high input impedance makes it useful for radio applications.
This circuit was obtained in documentation on medical applications from 1966. The circuit is used in...
This circuit, which appears from other sources on this site, converts a voltage into a current....
This interesting circuit makes the needle of a microammeter oscillate at random, imitating a...