| 摘要 |
A circuit for generating a composite timing signal in a television receiver comprises a gate pulse generating circuit, and a voltage divider coupled across a fixed voltage source. The composite signal comprises a first pulse developed at an output of the voltage divider during television signal horizontal and vertical blanking intervals, and a second pulse developed by the gate pulse circuit during a portion of the horizontal and vertical blanking intervals and superimposed on the first pulse. A switching device coupled to the voltage divider responds to horizontal and vertical timing control signals applied via signal coupling circuits for enabling the voltage divider to develop the first pulse. The level of the first pulse is predictably determined by the voltage divider substantially independent of the amplitudes of the horizontal and vertical timing signals, and the values of circuit components included in the timing control signal coupling circuits.
|
