1310/1550nm 1mW output power CW power stability: ±0.03db (24h) Internal digital modulation The Agilent 81654A Fabry-Perot laser source is a dual-wavelength module to be used in conjunction with optical power meter modules for insertion loss, optical return loss and PDL measurement of broadband components and fiber. The Agilent 81654A Fabry-Perot laser module is insensitive to back reflections and is stabilized for short and long-term applications.