| 摘要 |
PURPOSE:To make a mobile frequency stable for a frequency phase synchronizing circuit by setting a control voltage inputted to a VSYNC generating means to a constant value at moving state. CONSTITUTION:Upon the detection of a frequency phase synchronizing circuit brought into the moving state, a control voltage switching signal (CXVC) generating means 16 sets a control voltage switching signal CXVC fed to a synchronous clock (VSYNC) generating means 15 and supplies the result to a control voltage (VC) switching means 18. When the signal CXVC is turned on, the switching means 18 supplies the reference control voltage of a reference control voltage source 17 to the VSYNC generating means 15, which is stably in moved at a constant frequency corresponding to the reference control voltage being the constant value. Thus, the mobile frequency of the frequency phase synchronizing circuit is made stable. |
