US3678183A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic frequency control of voltage variable reactance tuned receivers
Assignee: Lanteris Space LLC
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Filing: 1971-04-26
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Granted: 1972-07-18
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Expires: 1991-04-26
Abstract
Abstract A jogging circuit is incorporated into the automatic frequency control system associated with touch-button tuning of television receivers that contain voltage variable reactance tuning elements. Each time a touch button is operated, the voltage applied to the tuning system is made to change first to a predetermined value and then return to its preset value. Thus the receiver tuning will be varied, each time a new channel is selected, so that the preset tuning is always approached from the same direction. This avoids the possibility of spurious automatic frequency control locking to the wrong signal carrier. In a television receiver, the television picture carrier is the desired reference. If the local oscillator is operated above the picture carrier, the local oscillator signal is jogged to a lower than normal frequency each time a touch-button is operated, and the preset tuning point is always approached from the low frequency side. Since the sound carrier is at the high frequency end of the television channel, spurious sound carrier locking is avoided.
Inventors
- 👤 Andrew P Montgomery
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:08
CPC Classifications
H; H03; H03J; H03J7/00; H03J7/02; H03J7/023; H03J7/04; H03J7/08; H03J7/12
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
90 words
In a superheterodyne television signal receiver having voltage variable reactance tuning elements varied by means of touch-button selected potentiometers energized from a regulated voltage power supply by means of electronic latching circuits and having automatic frequency control operating from a discriminator tuned to one of the receiver intermediate frequencies, said discriminator output signal controlling the output of said power supply, the improvement comprising: a circuit actuated by said touch-button for shifting the output voltage of said regulator in a give direction and then returning the voltage to its nominal value.
Claim 2
Dependent Claim
90 words
In a superheterodyne television signal receiver having voltage variable reactance tuning elements varied by means of touch-button selected potentiometers energized from a regulated voltage power supply by means of electronic latching circuits and having automatic frequency control operating from a discriminator tuned to one of the receiver intermediate frequencies, said discriminator output signal controlling the output of said power supply, the improvement comprising: a circuit actuated by said touch-button for shifting the output voltage of said regulator in a give direction and then returning the voltage to its nominal value.
Claim 3
Dependent Claim
21 words
The improvement of claim 1 wherein said regulator is shifted so as to decrease its output when said circuit is actuated.
Claim 4
Dependent Claim
155 words
In a touch-button actuated electronic latching system for tuning a television receiver employing voltage variable capacitor tuning, an improved automatic frequency control circuit comprising: a. a regulated power supply; b. a plurality of touch-buttons for actuating preset tuning for selected television channels; c. a plurality of electronic latches, one for each touch-button, each electronic latch comprising: a potentiometer, and a switching circuit for connecting said potentiometer to said regulated power supply in response to actuating one of said touch buttons; d. a discriminator tuned to an intermediate carrier frequency; e. means for controlling said regulated voltage in accordance with said discriminator output to achieve automatic frequency control of said receiver; and f. means responsive to the actuation of any one of said plurality of touch-buttons for introducing a brief voltage transient of predetermined polarity in the output of said discriminator whereby the receiver tuning frequency is momentarily changed to avoid spurious automatic frequency control locking.
Claim 5
Dependent Claim
155 words
In a touch-button actuated electronic latching system for tuning a television receiver employing voltage variable capacitor tuning, an improved automatic frequency control circuit comprising: a. a regulated power supply; b. a plurality of touch-buttons for actuating preset tuning for selected television channels; c. a plurality of electronic latches, one for each touch-button, each electronic latch comprising: a potentiometer, and a switching circuit for connecting said potentiometer to said regulated power supply in response to actuating one of said touch buttons; d. a discriminator tuned to an intermediate carrier frequency; e. means for controlling said regulated voltage in accordance with said discriminator output to achieve automatic frequency control of said receiver; and f. means responsive to the actuation of any one of said plurality of touch-buttons for introducing a brief voltage transient of predetermined polarity in the output of said discriminator whereby the receiver tuning frequency is momentarily changed to avoid spurious automatic frequency control locking.
Claim 6
Dependent Claim
41 words
The improved automatic frequency control circuit of claim 3 wherein said discriminator is tuned to the video intermediate frequency carrier and said means responsive to the actuation of any one of said plurality of touch-buttons momentarily lowers the receiver tuning frequency.
Claim 7
Dependent Claim
142 words
In a television receiver of the superheterodyne type adapted to receive video and accompanying sound transmissions in any selected one of a plurality of channels, voltage variable capacitor tuning means for tuning at least the local oscillator of said receiver, manually operated station selection means for selecting any one of said channels, means responsive to said manually operated station selection means for applying to said voltage variable capacitor tuning means a predetermined voltage representative of the channel selected, automatic frequency control means tuned to the video carrier for adjusting said predetermined voltage to effect automatic fine tuning control, and means responsive to each actuation of said station selection means for adding to said predetermined voltage a brief voltage transient of predetermined polarity, whereby tuning of each selected channel is approached from the video rather than the sound carrier side of said channel.
Claim 8
Dependent Claim
142 words
In a television receiver of the superheterodyne type adapted to receive video and accompanying sound transmissions in any selected one of a plurality of channels, voltage variable capacitor tuning means for tuning at least the local oscillator of said receiver, manually operated station selection means for selecting any one of said channels, means responsive to said manually operated station selection means for applying to said voltage variable capacitor tuning means a predetermined voltage representative of the channel selected, automatic frequency control means tuned to the video carrier for adjusting said predetermined voltage to effect automatic fine tuning control, and means responsive to each actuation of said station selection means for adding to said predetermined voltage a brief voltage transient of predetermined polarity, whereby tuning of each selected channel is approached from the video rather than the sound carrier side of said channel.
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) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |