Apparatus, systems and methods for separating a selected optical signal wavelength component from a plurality of optical signal wavelength components of an aggregate optical signal, and for passing the selected optical signal wavelength component while suppressing the remaining wavelength components are provided. Generally, the apparatus provides an optical signal wavelength selective element enabling output of a selectable optical signal wavelength component. The system contains a fiber optic cable carrying an optical signal, an optical signal measurement apparatus to measure optical signal characteristics, and an optical wavelength selector to pass the selected optical signal wavelength component to the optical signal measurement apparatus.