The Agilent / HP 16344A 1 MHz Phase Standard is specially designed for calibration of instruments capable of phase difference measurements. It outputs, from the front-panel, two precise, stable 1 MHz sine waves of equal amplitude. The phase difference between these two signals can be shifted from 0° to 360° in -22.5° steps, thus providing a known phase difference for the test instruments to measure. For a test instrument requiring phase-locking between its internal signal source and the test input signals, the 16344A outputs, from the rear-panel, a 1 MHz square wave. This signal is applied to the test instrument's external reference input connector.