The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 04, 2001
Filed:
Dec. 28, 1999
Jiening Ao, Suwanee, GA (US);
Steven E. Blashewski, Duluth, GA (US);
John W. Brickell, Lawrenceville, GA (US);
Pieter G. Ibelings, Norcross, GA (US);
Scientific-Atlanta, Inc., Lawrenceville, GA (US);
Abstract
Voltage-induced hum modulation in an amplifier can be caused when shunt capacitors begin to saturate and enter their non-linear region of operation. Bypass coils within the amplifier are magnetically coupled to the shunt capacitors and exacerbate hum modulation by coupling additional energy to the shunt capacitors. By introducing a resistance (R) in series with the shunt capacitors (C), energy that would normally be stored in the shunt capacitors (C) is dissipated. As a result, the shunt capacitors (C) remain in their linear region of operation more often and present a more stable impedance. The resistor (R) is especially beneficial at reducing hum modulation at the resonant frequency of the shunt capacitors (C), when the transfer of energy from the bypass coils (L) is at a maximum.