US3758710A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ducer and/or recorder time base error correction system,including converter,for video repro
Assignee: CARTRIDGE TELEVISION Inc
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Filing: 1972-03-09
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Granted: 1973-09-11
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Expires: 1992-03-09
Abstract
Abstract Disclosed herein is a system for compensating for time base errors existing in helical scan video recorders. On playback horizontal synchronizing signals are stripped from the composite video output of the recorder-reproducer and the stripped horizontal sync signals are applied to the phase detector element of a phase lock loop. To another input of the phase lock loop is applied the synchronizing signal of a simulated television receiver horizontal scanning system. The resultant control signal is filtered and utilized to control the horizontal oscillator in the simulated horizontal scanning system. It is also applied to an analog to digital converter which converts the analog voltage into variable delays, preferably in binary steps. The delays are inserted between the video output of the recorder-reproducer and the input of an actual television receiver monitor.
Inventors
- 👤 P Crosno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:35
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/76; H04N5/91; H04N5/93; H04N5/95
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
191 words
A circuit for correcting time base errors appearing in the output of a video tape reproducing device, which output is adapted to be applied in a video signal path to a television receiver readout having a horizontal scanning system, said circuit comprising: Means for stripping horizontal synchronizing signals from said output, a local oscillator, detecting means having inputs coupled to the stripping means and the local oscillator and adapted to have applied thereto the stripped horizontal synchronizing signals and the output of said local oscillator to produce a resultant analog error signal, means for filtering said analog error signal and utilizing it to control said local oscillator, the ensemble of said local oscillator and said detecting means and said filtering means being proportioned to simulate in parameters and operation the horizontal scanning system of said television receiver readout, analog-to-digital converter means for converting said analog error signal into a digital control signal, a plurality of delay lines, and means intercoupling the converter and the delay lines for switching the delay lines into the video path in accordance with said digital control signal, thereby correcting time base errors appearing in said output.
Claim 2
Dependent Claim
191 words
A circuit for correcting time base errors appearing in the output of a video tape reproducing device, which output is adapted to be applied in a video signal path to a television receiver readout having a horizontal scanning system, said circuit comprising: Means for stripping horizontal synchronizing signals from said output, a local oscillator, detecting means having inputs coupled to the stripping means and the local oscillator and adapted to have applied thereto the stripped horizontal synchronizing signals and the output of said local oscillator to produce a resultant analog error signal, means for filtering said analog error signal and utilizing it to control said local oscillator, the ensemble of said local oscillator and said detecting means and said filtering means being proportioned to simulate in parameters and operation the horizontal scanning system of said television receiver readout, analog-to-digital converter means for converting said analog error signal into a digital control signal, a plurality of delay lines, and means intercoupling the converter and the delay lines for switching the delay lines into the video path in accordance with said digital control signal, thereby correcting time base errors appearing in said output.
Claim 3
Dependent Claim
24 words
A circuit in accordance with claim 1 in which the delay lines are proportioned to be switched into the video path in binary steps.
Claim 4
Independent Claim
91 words
The method of correcting time Base errors appearing in the output of a tape reproducing device, which output is adapted to be applied in a video signal path to a television receiver readout comprising: the steps of stripping horizontal synchronizing signals from said output, developing a horizontal scanning signal which simulates the horizontal scanning signal of said television receiver readout, comparing the horizontal synchronizing signals and the horizontal scanning signals to develop an analog control signal, and introducing signal delays in said path as a function of said digital control signal.
Claim 5
Independent Claim
91 words
The method of correcting time Base errors appearing in the output of a tape reproducing device, which output is adapted to be applied in a video signal path to a television receiver readout comprising: the steps of stripping horizontal synchronizing signals from said output, developing a horizontal scanning signal which simulates the horizontal scanning signal of said television receiver readout, comparing the horizontal synchronizing signals and the horizontal scanning signals to develop an analog control signal, and introducing signal delays in said path as a function of said digital control signal.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-10 | 1977-03-12 | 1977-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-10 | 1981-03-12 | 1981-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-10 | 1985-03-12 | 1985-09-11 | $7700.00 | Window Closed / Lapsed |