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 is from a 1977 Signetics manual. BC107 transistors can be replaced with BC547 and...
This variable power supply circuit was found in a German publication from the 1980s. The circuit is...
This simple control circuit was found in American documentation from the 1990s. | Clique na imagem...