Patent US4001709A successfully refreshed from Google Patents.
US4001709A
Expired / Lapsed
US
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Active dual channel tuning control
Assignee: Individual
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Filing: 1975-09-30
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Granted: 1977-01-04
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Expires: 1995-09-30
Abstract
Abstract An active dual channel tuning control particularly useful for television and stereo applications has two independently adjustable channels. For example, each channel for stereo has an input for receiving a decoded signal which represents the left or right channel information. Each channel additionally has a feedback amplifier with an adjustably turned output to permit highly selective tuning and impedance matching to the following amplification stages. Switching networks are provided for reversing the channel outputs as well as for selectively inhibiting either of the channel outputs in either the normal or reversed channel condition.
Inventors
- 👤 Matthew Clinkscales
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:13
CPC Classifications
H; H03; H03G; H03G5/00; H03G5/02; H03G5/14; H03F; H03F3/00; H03F3/68; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/1646
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
110 words
A dual channel tuning circuit comprising two input terminal means each for receiving a different informational electrical signal; an amplifier provided in each channel and having an input and an output; switching means between said input terminal means and said amplifier inputs for selectively reversing said input terminal means with respect to each of said amplifier inputs and for selectively inhibiting said signals from being applied to said amplifier inputs; adjustable impedance means associated with each amplifier; and feedback means provided between each amplifier output and one of said input terminals for enhancing the tuning and impedance matching to signal processing circuitry that follows when said impedance means is adjusted.
Claim 2
Dependent Claim
110 words
A dual channel tuning circuit comprising two input terminal means each for receiving a different informational electrical signal; an amplifier provided in each channel and having an input and an output; switching means between said input terminal means and said amplifier inputs for selectively reversing said input terminal means with respect to each of said amplifier inputs and for selectively inhibiting said signals from being applied to said amplifier inputs; adjustable impedance means associated with each amplifier; and feedback means provided between each amplifier output and one of said input terminals for enhancing the tuning and impedance matching to signal processing circuitry that follows when said impedance means is adjusted.
Claim 3
Dependent Claim
42 words
A tuning circuit as defined in claim 1, wherein each amplifier comprises a transistor having the base thereof connected to an associated one of said input terminal means and the collector thereof connected to an associated one of said adjustable impedance means.
Claim 4
Dependent Claim
25 words
A tuning circuit as defined in claim 1, wherein each adjustable impedance means comprises a plurality of different impedances selectively connectable to an associated amplifier.
Claim 5
Dependent Claim
33 words
A tuning circuit as defined in claim 3, wherein each adjustable impedance means includes a multi-pole switch for selectively switching one of said associated impedances into operative tuning portions of an associated amplifier.
Claim 6
Dependent Claim
17 words
A tuning circuit as defined in claim 3, wherein said impedances include both reactive and resistive components.
Claim 7
Dependent Claim
23 words
A tuning circuit as defined in claim 1, wherein each feedback means comprises a capacitor connected between an associated amplifier output and input.
Claim 8
Dependent Claim
15 words
A tuning circuit as defined in claim 1, wherein each channel has a transformer output.
Claim 9
Dependent Claim
55 words
A tuning circuit as defined in claim 1, wherein said switching means includes a double-pole, double-throw switch connected to connect said input terminal means to the associated amplifiers in one position of said switch, and to connect said input terminal means to the other than said associated amplifiers in the other position of said switch.
Claim 10
Dependent Claim
82 words
A tuning circuit as defined in claim 1, wherein said switching means includes a double-pole, three-position switch connected in each of said channels to permit the application of a signal to only one of said amplifiers in a first position of said switch, to permit the application of a signal only to the other of said amplifiers in a second position of said switch, and to permit the application of signals to both said amplifiers in a third position of said switch.
Claim 11
Dependent Claim
29 words
A tuning circuit as defined in claim 1, further comprising volume control means in each of said channels for modifying the magnitudes of said signals at said amplifier output.
References Cited (Backward Citations)
DE1074085B
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-01-04 | 1980-07-05 | 1981-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-04 | 1984-07-05 | 1985-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-04 | 1988-07-05 | 1989-01-04 | $7700.00 | Window Closed / Lapsed |