EXFOs FTB-5240B is a high-resolution, high-precision optical spectrum analyzer (OSA) designed for ultra-dense WDM applications. Its built-in reference source not only provides better wavelength accuracy, but also makes OSA calibration more resistant to shock. Easily characterize DWDM signals, EDFAs, DFBs and spectral transmittance thanks to automated tests in the 1250 to 1650 nm range. Housed in the FTB-400 platform, the FTB-5240B offers the impressive optical performance of a lab-quality instrument in a field-ready, multitasking portable unit. Combine the FTB-5240B OSA with the FTB-9310 Channel Selector and FTB-8000 SONET/SDH analyzer and run EXFOs Lambda Auto-Sweeper integrated test application, which allows network service providers and carriers to automatically and simultaneously perform both optical- and protocol-layer measurements on 2.5 and 10 Gb/s systems.