NOISE SUPPRESSION CIRCUIT FOR AUDIO SIGNAL

• Main Authors: ITOU SHIGEYUKI, WATAYA YOSHIZUMI
• Format: Patent
• Language: English
• Published: 29.10.1982
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS; PICTORIAL COMMUNICATION, e.g. TELEVISION; TRANSMISSION

PURPOSE:To suppress noise to an extent without hindrance practically, with a simple constitution, by linearly interpolating a signal level before and afte the production of noise through the utilization that the time interval of noise generated at reproducing track changeover is constant. CONSTITUTION:A pulse having a width corresponding to a prescribed noise period in the time width of track changeover is generated from a monostable multivibrator 14 with a track changeover signal from a terminal 13 to trigger a monostable multivibrator 15 generating the same width, and a Q output of the multivibrator 15 controls the turning on of a switch circuit 11 and a Q' output controls the turning off of switch circuits 3-5. A voltage of a capacitor 8 with the audio input just before the generation of noise due to track changeover from a terminal 1 is subtracted with a voltage of a capacitor 7 in response to the audio input just after the generation of noise via a delay circuit 2 at a subtraction circuit 9 to control the charge/discharge of a capacitor 6 via a variable current source 10. Linear interpolation is made by utilizing that the time width of noise is constant in the signal level just before the generation of noise, allowing to suppress noise to an extent that gives no hindrance practically with a simple constitution.