  One of the prominent platforms for quantum technologies, cold atoms require
reliable laser systems. We present the design, implementation, and
characterization of a simple, compact, and economical laser system at 780 nm,
entirely based on fiber components. Two semiconductor lasers at 1560 nm are
amplified in a single Erbium-doped fiber amplifier and frequency-doubled in a
periodically-poled lithium niobate crystal. We characterize the amplitude noise
and the linewidths of the lasers, as well as the SHG efficiency. With a rms
relative amplitude noise of 3$\times$10$^{-4}$ at 1 s and linewidths below 1
MHz, our system is suitable for cooling and trapping of Rb atoms.
