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 provides an output voltage approximately 2 times that of the input voltage. The...
This current meter with many scales was found in a 80s American documentation. The operational amplifier...
The transformer of this experimental circuit, which appears in other versions on the website, is...