Title:
TELEVISION SIGNAL CLAMPING CIRCUIT
Document Type and Number:
Japanese Patent JPS5997273
Kind Code:
A
Abstract:
A black-level clamp for a signal derived from a transducer such as a camera tube includes a controllable voltage offset generator such as a series capacitor or an amplifier. The television signal is sampled during the horizontal sync interval to produce a control signal indicative of the current black-level signal, and the control signal is applied to adjust the charge on the series capacitor to place one plate at a reference voltage or is compared with a reference level to produce a further control signal for adjusting the offset of the amplifier. In either case, drift of the reference voltage which may perturb the operation of the clamp is reduced by deriving the reference voltage from the television signal at times within the vertical blanking interval.
Inventors:
CHIYAARUZU RANGUDON ORUSON
JIYON FURANSHISU MONAHAN
JIYON FURANSHISU MONAHAN
Application Number:
JP20246783A
Publication Date:
June 05, 1984
Filing Date:
October 27, 1983
Export Citation:
Assignee:
RCA CORP
International Classes:
H04N5/18; (IPC1-7): H04N5/16
Attorney, Agent or Firm:
Satoshi Shimizu