GB768678A - Improvements in or relating to synchronising circuits - Google Patents

Improvements in or relating to synchronising circuits

Info

Publication number
GB768678A
GB768678A GB2400053A GB2400053A GB768678A GB 768678 A GB768678 A GB 768678A GB 2400053 A GB2400053 A GB 2400053A GB 2400053 A GB2400053 A GB 2400053A GB 768678 A GB768678 A GB 768678A
Authority
GB
United Kingdom
Prior art keywords
frequency
valve
phase
aug
sensitivity
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.)
Expired
Application number
GB2400053A
Inventor
Eric Lawrence
Casling White
William Spencer Percival
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.)
EMI Ltd
Electrical and Musical Industries Ltd
Original Assignee
EMI Ltd
Electrical and Musical Industries 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
Application filed by EMI Ltd, Electrical and Musical Industries Ltd filed Critical EMI Ltd
Priority to GB2400053A priority Critical patent/GB768678A/en
Publication of GB768678A publication Critical patent/GB768678A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/04—Synchronising
    • H04N5/12—Devices in which the synchronising signals are only operative if a phase difference occurs between synchronising and synchronised scanning devices, e.g. flywheel synchronising
    • H04N5/126—Devices in which the synchronising signals are only operative if a phase difference occurs between synchronising and synchronised scanning devices, e.g. flywheel synchronising whereby the synchronisation signal indirectly commands a frequency generator
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
    • H03L7/00—Automatic control of frequency or phase; Synchronisation
    • H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
    • H03L7/08—Details of the phase-locked loop

Landscapes

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

Abstract

768,678. Automatic synchronizing control systems. ELECTRIC & MUSICAL INDUSTRIES, Ltd. Aug. 31, 1954 [Aug. 31, 1953], No. 24000/53. Class 38 (4). An oscillator 2 is synchronized relative to a pulse source 1, e.g. in a television flywheel scanning system, by applying both outputs to a phase discriminator 5 whose smoothed output controls a reactance valve 10 stabilizing through a condenser 11 the frequency and phase generated. According to the invention the sensitivity of the valve 10 is increased for a frequency range, e.g. round 50 c/s., of the control voltage at which the latter is most subject to disturbance, e.g. due to phase modulation of the transmitted synchronizing pulses at this mains frequency. To this end the reactance valve 10, or a preceding amplifying valve, may have a negative feedback path 17 including a parallel T or other filter 21 strongly attenuating this frequency so that the negative feedback is then inoperative. Or the phase discriminator output filter may include a parallel resonant circuit 26, 27 connected in series with one, 23, of the smoothing condensers 23, 25, to reduce the effectiveness of the smoothing at the resonant frequency. Sensitivity of control may also be arranged to increase at harmonics of the mains frequency.
GB2400053A 1953-08-31 1953-08-31 Improvements in or relating to synchronising circuits Expired GB768678A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB2400053A GB768678A (en) 1953-08-31 1953-08-31 Improvements in or relating to synchronising circuits

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2400053A GB768678A (en) 1953-08-31 1953-08-31 Improvements in or relating to synchronising circuits

Publications (1)

Publication Number Publication Date
GB768678A true GB768678A (en) 1957-02-20

Family

ID=10204785

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2400053A Expired GB768678A (en) 1953-08-31 1953-08-31 Improvements in or relating to synchronising circuits

Country Status (1)

Country Link
GB (1) GB768678A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1146916B (en) * 1961-08-24 1963-04-11 Standard Elektrik Lorenz Ag Circuit arrangement for suppressing the fluctuations in the picture frame position when reproducing television pictures
GB2122441A (en) * 1982-05-20 1984-01-11 Pioneer Video Corp Phase-locked loop lock-detecting circuit

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1146916B (en) * 1961-08-24 1963-04-11 Standard Elektrik Lorenz Ag Circuit arrangement for suppressing the fluctuations in the picture frame position when reproducing television pictures
GB2122441A (en) * 1982-05-20 1984-01-11 Pioneer Video Corp Phase-locked loop lock-detecting circuit

Similar Documents

Publication Publication Date Title
GB752390A (en) Improvements in or relating to circuits for automatic frequency correction
US2282092A (en) Frequency modulation receiver
US2188611A (en) Impulse generator
US2484763A (en) Harmonic-frequency generator
GB507454A (en) Improvements in frequency stabilisation arrangements for oscillation generators
GB788114A (en) Improvements relating to frequency and phase control systems
GB768678A (en) Improvements in or relating to synchronising circuits
GB841378A (en) Frequency-control systems
GB471185A (en) Improvements in or relating to arrangements for controlling a cathode ray tube
US2453988A (en) Automatic frequency control
GB664407A (en) Television receiving apparatus
US2631239A (en) Automatic frequency control system
US1976457A (en) Method of and means for removing modulation from a modulated wave
GB1466288A (en) Discrimination circuit arrangements
GB603367A (en) Super-regenerative receiver
US2469174A (en) Pulse-modulated wave-signal generator
GB708225A (en) Improvements in or relating to circuits for synchronising an oscillator to a controloscillation
GB569327A (en) Improvements relating to generators of frequency modulated oscillations
US2678386A (en) Frequency modulation receiver
GB615987A (en) Improvements in or relating to circuits for amplifying electrical oscillations
SU69054A1 (en) Radio
US2343745A (en) Direct-current amplifier stage
US2395573A (en) Modulating system
GB568053A (en) An arrangement for automatically influencing the tuning of oscillation circuits
SU422061A1 (en) DEVICE FOR ADJUSTING VIBRATING CIRCUITS