This circuit was found in a General Electric documentation from 1966. It uses discrete components of the time that can be replaced by modern equivalents.
This low noise circuit was obtained from a 1980s US RF publication. Transistors used are uncommon...
The scratch is the noise of scratching or scrape that occurs when scratched vinyl records are...
We found this circuit in the magazine Eletcronics Now of July 1994. The power supply is according to...