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This audio filter was found in the August 1993 issue of Radio Electronics magazine. It cuts low and high frequencies corresponding to rumble and scratch noises that occur on turntables.
This circuit was found in documentation from the 1980s. The circuit uses several components of the...
The National Semiconductor LM143 integrated circuit consists of a high voltage operational...
Found in a 1970s documentation, this mini-organ toy circuit makes use of an integrated circuit from...