FR2264446A1 - Digital time-base correction for television receivers - uses analogue-to-digital conversion of picture signal controlled by oscillator - Google Patents

Digital time-base correction for television receivers - uses analogue-to-digital conversion of picture signal controlled by oscillator

Info

Publication number
FR2264446A1
FR2264446A1 FR7508017A FR7508017A FR2264446A1 FR 2264446 A1 FR2264446 A1 FR 2264446A1 FR 7508017 A FR7508017 A FR 7508017A FR 7508017 A FR7508017 A FR 7508017A FR 2264446 A1 FR2264446 A1 FR 2264446A1
Authority
FR
France
Prior art keywords
oscillator
digital
analogue
television receivers
base correction
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
FR7508017A
Other languages
French (fr)
Other versions
FR2264446B3 (en
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Quantel Ltd
Original Assignee
Quantel Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GB1179374A external-priority patent/GB1465314A/en
Application filed by Quantel Ltd filed Critical Quantel Ltd
Publication of FR2264446A1 publication Critical patent/FR2264446A1/en
Application granted granted Critical
Publication of FR2264446B3 publication Critical patent/FR2264446B3/fr
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/79—Processing of colour television signals in connection with recording
    • H04N9/87—Regeneration of colour television signals
    • H04N9/89—Time-base error compensation
    • H04N9/896—Time-base error compensation using a digital memory with independent write-in and read-out clock generators

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Television Signal Processing For Recording (AREA)
  • Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)

Abstract

A digital time base correction system for television receivers is based upon analogue to digital conversion followed by memory storage. A digital to analogue converter is then used to operate on the memory output. The main feature of the system relates to the method used for controlling a triggered oscillator that is linked with the analogue-to-digital converter. The oscillator consists of an amplifier with a feedback loop with a time constant determined by an R-C network. Depending upon the state of an FET the oscillator operational period may be controlled. When the output of the picture synchronisation circuit goes low a bistable becomes zero and the FET opens allowing the oscillator to run. The oscillator output changes the state of a counter until a predetermined count is reached.
FR7508017A 1974-03-16 1975-03-14 Digital time-base correction for television receivers - uses analogue-to-digital conversion of picture signal controlled by oscillator Granted FR2264446A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB1179374A GB1465314A (en) 1974-03-16 1974-03-16 Digital time base correctors for television equipment
GB1179474 1974-03-16

Publications (2)

Publication Number Publication Date
FR2264446A1 true FR2264446A1 (en) 1975-10-10
FR2264446B3 FR2264446B3 (en) 1977-11-18

Family

ID=26248522

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7508017A Granted FR2264446A1 (en) 1974-03-16 1975-03-14 Digital time-base correction for television receivers - uses analogue-to-digital conversion of picture signal controlled by oscillator

Country Status (3)

Country Link
CA (1) CA1018646A (en)
DE (1) DE2511352A1 (en)
FR (1) FR2264446A1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2321223A1 (en) * 1975-08-14 1977-03-11 Rca Corp SYNCHRONIZATION SYSTEM
FR2358054A1 (en) * 1976-07-05 1978-02-03 Sony Corp REFERENCE SIGNAL GENERATOR TO CORRECT THE TIME BASE
EP0179590A2 (en) * 1984-10-20 1986-04-30 Sony Corporation Phase control circuits for timebase correctors
EP0189195A2 (en) * 1985-01-25 1986-07-30 Hitachi, Ltd. Apparatus for correcting time base error of video signal
EP0283263A2 (en) * 1987-03-16 1988-09-21 Pioneer Electronic Corporation Video format signal processing system

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1571124A (en) * 1976-02-19 1980-07-09 Quantel Ltd Video synchroniser or time base corrector with velocity compensation

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2321223A1 (en) * 1975-08-14 1977-03-11 Rca Corp SYNCHRONIZATION SYSTEM
FR2358054A1 (en) * 1976-07-05 1978-02-03 Sony Corp REFERENCE SIGNAL GENERATOR TO CORRECT THE TIME BASE
EP0179590A2 (en) * 1984-10-20 1986-04-30 Sony Corporation Phase control circuits for timebase correctors
EP0179590A3 (en) * 1984-10-20 1987-06-24 Sony Corporation Phase control circuits for timebase correctors
EP0189195A2 (en) * 1985-01-25 1986-07-30 Hitachi, Ltd. Apparatus for correcting time base error of video signal
EP0189195A3 (en) * 1985-01-25 1988-02-03 Hitachi, Ltd. Apparatus for correcting time base error of video signal
EP0283263A2 (en) * 1987-03-16 1988-09-21 Pioneer Electronic Corporation Video format signal processing system
EP0283263A3 (en) * 1987-03-16 1989-11-29 Pioneer Electronic Corporation Video format signal processing system

Also Published As

Publication number Publication date
DE2511352A1 (en) 1975-09-18
CA1018646A (en) 1977-10-04
FR2264446B3 (en) 1977-11-18

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