SyncCV is one high-precision comparator for remote time comparison based on satellite Common-View technology. It takes national standard time UTC(NTSC) at reference to measure the deviation between user time and national standard time, to trace the source to UTC, and to display the result graphically in real time, in order to calibrate the user time. It can be used to perform high-precision time measurement and obtain the calibration amount of time signals at various locations so as to synchronize the time of all locations. It also effectively analyzes and evaluates the stability and accuracy of time signal at certain location as well as the deviation with national time. It is applicable in time measurement of synchronous devices like PRTC and ePRTC, in time deviation calibration, or in the long-term monitoring of time deviation of high-precision time synchronous network.