  The rf distribution system for the linear collider requires stable
x-band(11.424GHz) rf phase signal over 25km length. In order to realize the
distribution system, a fiber optic link using a phase stabilized optical fiber
was tested. The phase stabilized optical fiber has been employed at LEP, KEKB,
etc.. This paper describes the hardware system and result of the preliminary
test of the feed back system for stabilization of the phase change.
