| 摘要 |
PURPOSE:To decrease the effect of a weak electric field on a screen and to stabilize the vertical synchronism, by reducing the mutual effect between a synchronizing separation signal operating an AFC comparison circuit and the synchronizing separation signal applied to an integration circuit with a transistor (TR) circuit. CONSTITUTION:A composite video signal impressed from a terminal 1 is separated synchronizingly at TRsQ1,Q2 and applied to the AFC comparison circuit from a terminal 2. Further, the base of a TRQ4 is connected to the collector of the TRQ1, the emitter of the TRQ4 is connected to a power supply line via diode D3, the collector is connected to the base of a TRQ5 and to the emitter of the TRQ5 via a resistor R7. Further, the collector of the TRQ5 is connected to the power supply line, the emitter is grounded via a resistor R8 and an output of the terminal 3 is given to an integration circuits. Thus, the synchronizing separation signal applied to the terminal 2 and the synchronizing separation signal outputted from the terminal 3 are applied to the TRQ4 having a common base to the TRQ2, allowing to hardly give a mutual effect. |
