  A compact green astro-comb with 43-GHz repetition rate is developed based on
a Ti:Sapphire optical frequency comb (OFC) and a mode-selecting cavity. The
OFC's large repetition rate of 1.6 GHz eases the requirements for the
mode-selecting cavity. Unnecessary frequency-modes of the OFC are suppressed
down to $5 \times 10^{-4}$ at 535 nm - 550 nm using a single mode-selecting
cavity with 70-MHz linewidth. The radial velocity precision $\sigma \sim 1.4$
m/s is achieved at the High Dispersion Echelle Spectrosraph for the Okayama
188-cm telescope of the National Astronomical Observatory of Japan using our
astro-comb. With further improvements of the mode-selecting cavity and removal
of fiber modal noises, our system will provide a simple, compact, and precise
astro-comb setup in visible wavelength region.
