| 摘要 |
PURPOSE:To improve the performance and the reliability of a television set by connecting a squelch holding circuit to hold the squelch-state when the input signal is cut off for a specified time on the output-side of a voltage comparator, and controlling to turn off a switch inserted on the output-side of a reception circuit by means of an output from said holding circuit. CONSTITUTION:The squelch holding circuit 4 added to the output-side of narrow- band squelch detectors 1-3, holds the state when the input signal is cut off (squelch occurring) for a specified time (sufficiently longer than the period of horizontal synchronization frequency), and continues not to act for said time even when a signal is inputted. A resistor 5 and a capacitor 6 in this circuit, determine the time constant of this circuit. In such a way, the removal of the interference due to neiboring channels from an FM television signal is upgraded.
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