US4353088A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coding and decoding system for video and audio signals
Assignee: TV/COM TECHNOLOGIES Inc
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Filing: 1980-05-14
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Granted: 1982-10-05
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Expires: 2000-05-14
Abstract
Abstract A coding and decoding system for video signals includes means at the transmitter for applying sine wave amplitude modulation of approximate line frequency to the aural carrier to prevent the chrominance subcarrier from providing receiver synchronization.
Inventors
- 👤 Pieter den Toonder
- 👤 Pieter J. Fondse
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:50
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/16; H04N7/167; H04N7/171; H04N7/1713
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
62 words
Means for coding video and audio signals including: (a) means for suppressing synchronizing information during video horizontal blanking intervals, (b) means for inserting digital sound data and decoder clock data into the suppressed horizontal blanking intervals, (c) and means for applying sine wave amplitude modulation of approximate line frequency to the aural carrier to prevent the chrominance subcarrier from providing receiver synchronization.
Claim 2
Dependent Claim
62 words
Means for coding video and audio signals including: (a) means for suppressing synchronizing information during video horizontal blanking intervals, (b) means for inserting digital sound data and decoder clock data into the suppressed horizontal blanking intervals, (c) and means for applying sine wave amplitude modulation of approximate line frequency to the aural carrier to prevent the chrominance subcarrier from providing receiver synchronization.
Claim 3
Dependent Claim
33 words
The coding system of claim 8 further characterized in that said sine wave amplitude modulation has a center frequency of 15.75 KHz and frequency variation therefrom on the order of about ±30 Hz.
References Cited (Backward Citations)
US2563448A
Cited
US2510046A
Cited
US2705740A
Cited
US3081376A
Cited
US3313880A
Cited
GB1104177A
Cited
US3485941A
Cited
US3530232A
Cited
GB1268136A
Cited
US4024575A
Cited
GB1505319A
Cited
US4081832A
Cited
US4095258A
Cited
US4215366A
Cited
US4245246A
Cited
US4295155A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-10-04 | 1986-04-05 | 1986-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-04 | 1990-04-05 | 1990-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-04 | 1994-04-05 | 1994-10-05 | $7700.00 | Window Closed / Lapsed |