Method and system for correcting time base errors in broadband signals

Abstract

Time base errors arising during the playback of a broadband signal previously stored in segments in a plurality of narrow-band channels with a first time transformation are corrected. Specifically, these signals are read out in turn from the narrow channels on the tape and applied at a slow rate to a plurality of buffer storages. They are read out from the buffer storages at a relatively fast rate, in sequence, so that the broadband signal is reconstituted. The broadband signal is then demodulated. For time base correction, the horizontal synchronization signals are separated from the reconstituted demodulated signal and their timing is compared to the timing of horizontal reference signals. A pulse is formed whose pulse width is equal to the time interval between occurrence of a horizontal synchronization pulse separated from the demodulated signal and the occurrence of the corresponding reference synchronization signal. The output of the clock generator controlling the readout from the buffer storages is delayed by a time interval equal to the pulse width. Further measures for decreasing residual errors are also specified. The measurement is carried on at the start of each line and after the signal has been reconstituted and demodulated and is thus present in a single channel.