Synchronized sampling controller for harmonic measurement

A synchronized sampling controller based on direct digital synthesis was developed in NIM China. It's used in the transfer standard for harmonic measurement. The working fundamental frequency of the controller is 45 to 65 Hz; the trigger output frequency is 11.5 kHz to 16.6 kHz due to the 256 times of the fundamental frequency. The resolution of the controller is less than 1 µHz.