The EBS-4022 Erbium Broadband Source is an extremely stable, flattened broadband source delivering 22 dBm in a 40-nm wide spectrum spanning the whole Erbium C band. It utilizes amplified spontaneous emission (ASE) from diode-pumped Erbium-doped fiber and a spectral shaping scheme which flattens the output to better than 1 dB from 1527 to 1567 nm.