| 摘要 |
A television ghost detector system is provided which receives a training signal component of the video signal followed by a signal interval which may contain a ghost of the training signal. The training signal activates the production of a varying search signal, which in turn initiates the production of a sequence of identification pulses. The identification pulses are compared with the video signal interval following the training signal, and a coincidence signal is produced when a ghost appears in time coincidence with an identification pulse. The coincidence signal causes the value of the varying search signal to be stored as an indication of the delay of the ghost with respect to the training signal. During subsequent training signal intervals, an identification pulse is produced only when the search signal attains the previously stored value, and the identification pulse is phase compared with the ghost to update the stored value to a more precise value. If the ghost is lost or disappears, the system reverts to its initial mode of operation.
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