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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 symmetrical 1.2 to 35 V source was found in a 1994 documentation. The integrated circuits are...
Found in a 90s Elektor, this mixer makes use of integrated circuits of the time. The supply must be...
This amplifier is specifically designed for portable radio and recorders with a 4 ohms load....