| 摘要 |
PURPOSE:To obtain a nearly constant horizontal screen position irrelevantly to an input signal mode. CONSTITUTION:A horizontal synchronous oscillation circuit system is equipped with a delay means 2 which delays a horizontal synchronizing signal 1 separated from an input video signal for horizontal screen position adjustment, an automatic frequency control means 3 which detects the phase difference between the delay horizontal synchronizing signal and flyback pulses 4 from a deflection system, and a voltage-controlled oscillator means 5 which is controlled with its detection output to generate a horizontal driving signal 6; and the free- running frequency control signal Vosc of the voltage-controlled oscillation means 5 is put together with a horizontal shift control signal Vshift controlling the delay quantity of the delay means 2 through a modulating means 7, whose modulation quantity is variable with a horizontal shift gain control signal Vmod. Then the horizontal shift gain controlled variable is usable as preset data for setting screen positions for various video signals. |
