Wave transmission lines and networks – Automatically controlled systems – With control of equalizer and/or delay network
Patent
1975-07-29
1977-08-02
Smith, Alfred E.
Wave transmission lines and networks
Automatically controlled systems
With control of equalizer and/or delay network
330 31, 330 86, 330145, H03H 704, H03H 1300
Patent
active
040399800
ABSTRACT:
In a bridge circuit consisting of diodes connected in each circuit branch in a forward direction from one of a pair of opposing terminals to another with a current flowing through these diodes, impedance between a second opposing pair of terminals varies in correspondence to the magnitude of the constant current. The invention utilizes this phenomenon and provides a voltage-controlled filter employing this bridge circuit as an impedance element for determining its frequency region and thereby being capable of controlling its frequency region by voltage controlling. A primary passive low-pass filter is described as a preferred example of the invention. The invention further provides a voltage-controlled filter having the bridge circuit provided in a negative feedback loop of an amplifier in an active filter circuit and thereby being capable of controlling selectivity Q by controlling the gain of the amplifier by voltage controlling. As a preferred example of this type of filter, a secondary active low-pass filter is described.
REFERENCES:
patent: 3229228 (1966-01-01), Reynolds
patent: 3469213 (1969-09-01), Baker
patent: 3643173 (1972-02-01), Whitten
patent: 3793593 (1974-02-01), Kennedy et al.
patent: 3805177 (1974-04-01), Risley
patent: 3911776 (1975-10-01), Beigel
Moore David K.
Nippon Gakki Seizo Kabushiki Kaisha
Smith Alfred E.
LandOfFree
Voltage-controlled filter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Voltage-controlled filter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Voltage-controlled filter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2302934