Patent US3777290A successfully refreshed from Google Patents.
US3777290A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Touch tuning and control circuits
Assignee: Meritor Inc
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Filing: 1972-05-24
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Granted: 1973-12-04
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Expires: 1992-05-24
Abstract
Abstract An electronic circuit for adjusting the volume and tone of an audio signal is controlled by appropriately bridging contacts included therein with a human finger or other conductive means. The length of time that a contact is bridged, or closed, determines the conductive state of a field effect transistor associated therewith. One such FET controls the gain of an audio amplifier whereby the amplitude of the audio signal is controlled. The conductive state of a second such FET controls the biasing voltage on a junction transistor to control the shunting of the high frequency components of the audio signals. The audio output is coupled to varactor tuning means so that a change in the conductive state of an FET changes the frequency to which the varactor tuning means is tuned.
Inventors
- 👤 C Pittman
- 👤 J Long
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:37
CPC Classifications
G; G11; G11C; G11C27/00; G11C27/02; G11C27/024; H; H03; H03G; H03G1/00; H03G1/0005; H03G1/0035; H03G9/00; H03G9/02; H03G9/12; H03G9/14; H03J; H03J3/00; H03J3/02; H03J3/16; H03J3/18; H03J3/185; Y; Y10; Y10S; Y10S323/00; Y10S323/904
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
168 words
A tuning circuit comprising, a varactor tuned circuit, a voltage source, resistance means connected across said voltage source, a field effect transistor having gate, drain, and source electrodes, a capacitor connected between said gate electrode and one side of said voltage source, one of said drain and source electrodes being connected to the other side of said voltage source, the other of said drain and source electrodes being connected through a resistor to said one side of said voltage source, said varactor tuned circuit being coupled to said resistor, contact means having conductive means spatially disposed from said resistance means, said conductive means extending substantially along the length of said resistance means, whereby pressure can be applied to a point on said conductive means to connect said gate electrode to a corresponding point on said resistance means, the voltage across said resistor being operatively dependent on the point on said conductive means to which pressure is applied to tune said varactor tuned circuit to a predetermined station frequency.
Claim 2
Dependent Claim
168 words
A tuning circuit comprising, a varactor tuned circuit, a voltage source, resistance means connected across said voltage source, a field effect transistor having gate, drain, and source electrodes, a capacitor connected between said gate electrode and one side of said voltage source, one of said drain and source electrodes being connected to the other side of said voltage source, the other of said drain and source electrodes being connected through a resistor to said one side of said voltage source, said varactor tuned circuit being coupled to said resistor, contact means having conductive means spatially disposed from said resistance means, said conductive means extending substantially along the length of said resistance means, whereby pressure can be applied to a point on said conductive means to connect said gate electrode to a corresponding point on said resistance means, the voltage across said resistor being operatively dependent on the point on said conductive means to which pressure is applied to tune said varactor tuned circuit to a predetermined station frequency.
Claim 3
Dependent Claim
28 words
The invention as set forth in claim 1 with the addition of a second capacitor connected between said gate electrode and said other side of said voltage source.
Claim 4
Dependent Claim
20 words
The invention as set forth in claim 1 wherein said field effect transistor is an insulated gate field effect transistor.
Claim 5
Dependent Claim
51 words
The invention as set forth in claim 1 wherein said conductive means comprises a continuous stRip of flexible conductive material adapted to be connected to said resistance means at any point along the length of said resistance means by the application of pressure at a corresponding point along said conductive material.
Claim 6
Dependent Claim
28 words
The invention as set forth in claim 4 with the addition of a second capacitor connected between said gate electrode and said other side of said voltage source.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-03 | 1977-06-04 | 1977-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-03 | 1981-06-04 | 1981-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-03 | 1985-06-04 | 1985-12-04 | $7700.00 | Window Closed / Lapsed |