US3699455A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic frequency control circuitry for a varactor tuner system
Assignee: GTE Sylvania Inc
•
Filing: 1971-01-20
•
Granted: 1972-10-17
•
Expires: 1991-01-20
Abstract
Abstract In a signal receiver employing a varactor tuner responsive to alterations in a potential source for effecting signal selection, an automatic frequency control (AFC) system includes a discriminator coupled to the varactor tuner and having an amplifier coupled to an IF amplifier stage and by way of a bias means to the potential source. Adjustment of the potential source to effect variations in signal selection also causes variations in amplification by the discriminator system which, in turn, varies the AFC correction applied to the varactor tuner.
Inventors
- 👤 William Frank Kruszewski
- 👤 Karol Siwko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:51
CPC Classifications
H; H03; H03J; H03J7/00; H03J7/02; H03J7/04; H03J7/08; H03J7/12
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
109 words
In a signal receiver having a varactor tuner coupled to an intermediate frequency (IF) amplifier means, an automatic frequency control (AFC) circuit comprising: discriminator means coupling said intermediate frequency (IF) amplifier means to said varactor tuner; bias means coupled to said discriminator means; and an adjustable potential source coupled to said varactor tuner and to said bias means whereby alterations in potential from said source effect selection of relatively high and low frequency signals by said varactor tuner and alteration of said bias means to effect development of relatively high and low AFC correction voltage by said discriminator means and increased and decreased ''''pull-in'''' ranges of said varactor tuner.
Claim 2
Dependent Claim
109 words
In a signal receiver having a varactor tuner coupled to an intermediate frequency (IF) amplifier means, an automatic frequency control (AFC) circuit comprising: discriminator means coupling said intermediate frequency (IF) amplifier means to said varactor tuner; bias means coupled to said discriminator means; and an adjustable potential source coupled to said varactor tuner and to said bias means whereby alterations in potential from said source effect selection of relatively high and low frequency signals by said varactor tuner and alteration of said bias means to effect development of relatively high and low AFC correction voltage by said discriminator means and increased and decreased ''''pull-in'''' ranges of said varactor tuner.
Claim 3
Dependent Claim
20 words
The AFC circuit of claim 1 including an AFC driver stage coupling said adjustable potential source to said bias means.
Claim 4
Dependent Claim
39 words
The AFC circuit of claim 1 wherein said bias means is in the form of a voltage divider connected intermediate said adjustable potential source and a potential reference level and coupled to said IF amplifier means and discriminator means.
Claim 5
Dependent Claim
46 words
The AFC circuit of claim 1 wherein said bias means includes a pair of resistors series connected intermediate said adjustable potential source and a potential reference level and having a junction intermediate said series connected resistors coupled to said IF amplifier means and said discriminator means.
Claim 6
Dependent Claim
40 words
The AFC circuit of claim 1 wherein said bias means includes a voltage divider coupling said adjustable potential source to a potential reference level and a varactor diode coupling said IF amplifier means and voltage divider to said discriminator means.
Claim 7
Dependent Claim
31 words
The AFC circuit of claim 1 wherein said discriminator means includes an amplifier stage coupled to said bias means and a discriminator stage coupling said amplifier stage to said varactor tuner.
Claim 8
Dependent Claim
89 words
Automatic frequency control (AFC) circuitry for a signal receiver comprising: a varactor tuner; intermediate frequency (IF) amplifier means coupled to said tuner; discriminator means coupling said IF amplifier means to said varactor tuner; bias means coupled to said discriminator means; and adjustable potentiaL source coupled to said varactor tuner and to said bias means whereby an increase in potential from said source increases the signal frequency selected by said tuner and increases the AFC correction voltage from said discriminator means which increases the ''''pull-in'''' range of said varactor tuner.
Claim 9
Dependent Claim
89 words
Automatic frequency control (AFC) circuitry for a signal receiver comprising: a varactor tuner; intermediate frequency (IF) amplifier means coupled to said tuner; discriminator means coupling said IF amplifier means to said varactor tuner; bias means coupled to said discriminator means; and adjustable potentiaL source coupled to said varactor tuner and to said bias means whereby an increase in potential from said source increases the signal frequency selected by said tuner and increases the AFC correction voltage from said discriminator means which increases the ''''pull-in'''' range of said varactor tuner.
Claim 10
Dependent Claim
28 words
The AFC circuit of claim 7 wherein said bias means is in the form of a voltage divider coupling said adjustable potential source to a potential reference level.
Claim 11
Dependent Claim
46 words
The AFC circuit of claim 7 wherein said bias means includes a pair of resistors series connected intermediate said adjustable potential source and a potential reference level with the junction of said series connected resistors coupled to said IF amplifier means and to said discriminator means.
Claim 12
Dependent Claim
38 words
The AFC circuitry of claim 7 wherein said bias means includes a voltage divider coupled to said adjustable potential source and to a potential reference level and a varactor diode coupling said voltage divider to said discriminator means.
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) | 1975-10-17 | 1976-04-17 | 1976-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-17 | 1980-04-17 | 1980-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-17 | 1984-04-17 | 1984-10-17 | $7700.00 | Window Closed / Lapsed |