Electrical transmission or interconnection systems – Nonlinear reactor systems – Parametrons
Patent
1982-09-30
1985-01-29
Miller, Stanley D.
Electrical transmission or interconnection systems
Nonlinear reactor systems
Parametrons
307516, 307529, 328167, 330302, 330306, H03H 1112, H03H 1116
Patent
active
044968590
ABSTRACT:
A notch filter system for eliminating a specific "stop" frequency from an AC electrical input signal, such as 60 Hz "hum" from an audio program signal. An L/C tuned circuit that is tuned to the stop frequency is used to develop a modified input signal that is in phase with the input signal only at the stop frequency. The two signals are amplitude-balanced and fed to the respective inputs of a balanced differential amplifier which is responsive to both input signal phase and amplitude differences so as to cancel the signals at the stop frequency where they have the same phase and amplitude but not at frequencies above and below the stop frequency where they differ in phase and amplitude.
REFERENCES:
patent: 3831117 (1974-08-01), Fletcher et al.
patent: 3838351 (1974-09-01), Hekimian
patent: 3936777 (1976-02-01), Rollett et al.
patent: 3936830 (1976-02-01), Overbury
patent: 4051385 (1977-09-01), Greenaway et al.
patent: 4107622 (1978-08-01), Toyomaki
patent: 4195265 (1980-03-01), Vali
patent: 4215280 (1980-07-01), Mahig
patent: 4245202 (1981-01-01), Huntley
Soliman et al., "A Universal Notch Filter", Circuit Theory and Applications, vol. 7, Wiley & Sons Ltd., Jan., 1979, pp. 139-142.
Clark, "Cancel 60 Hz and Other Noise", Electronic Design, vol. 20, Sep. 1976, pp. 74-79.
Panicker, "Simulated Inductance for Low Frequency Filter", Electronic Engineering, Nov., 1976, p. 19.
Haussmann et al., "Variable Filter Characteristics with an OP AMP", Electronic Engineering, Feb. 1972, pp. 41-42.
Barcus-Berry, Inc.
Gabriel Albert L.
Hudspeth David R.
Miller Stanley D.
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