The use of fiber optics to distribute UHF signals has been the topic in several studies. Some advantages of this approach are weight and volume savings compared with the use of waveguides and coaxial lines. We have developed a prototype fiber-optic system that modulates ultrastable time and frequency signals over fiber-optic lines. Some performance limitations of this technique are single sideband phase noise and signal-to-noise degradation. This paper will present experimental results including single sideband noise measurements and a discussion on the system's limitations.