With stable computer platform, full touchscreen operation and all-in-one design, SyncOne -A is a high-end full-featured instrument developped for time/frequency synchronization measurement. It supports a variety of time and clock measurements complied with latest specifications and ITU-T recommendations, and precisely measures, analyzes and evaluates time/frequency performance indexes. Also it meets the test requirements in 5G networks, which needs ultra-high-precision phase/frequency synchronization measurements. It can be used to take measurement in the process of R&D, Pilot, Calibrationn of time/frequency synchronization equipment. It is applicable in synchronous devices, 3G/4G mobile backhaul, telecom IP-Carrier/Access network, Intelligent Substation, Highways, Railway/Air transportation, Satellites, vessel calibration and traditional accounting system, in which full-featured time/frequency measurements are significantly required.