Special Features:

Nain: frequency and time; rackmount; clock and standby power supply included

Properties:

An item that can generate a fundamental frequency with a high degree of accuracy. Harmonics of this fundamental are then used as a reference point for checking throughout the radio spectrum. The standard may be stable crystal oscillator, noncrystal oscillator, tuning fork, atomic beam, molecular beam, gas cell, quantum mechanical resonator, or the like.