Scratch is the scratching noise that occurs mainly with old records. This high frequency noise is eliminated by the filter found in the February 1990 issue of Radio Electronics magazine.
This circuit was found in a 1972 RCA documentation. The transistor supports an equivalent as the...
The circuit shown below was obtained from the National Semiconductor Linear Applications Handbook...
Found in a 1960 Sylvania transistor manual, this circuit can be implemented with modern...