The fabrication and characterization of polymeric electrooptic modulators, made of a thermally crosslinkable polyurethane with Disperse Red 19 side chains, are summarized in this paper, Straight channel and Mach-Zehnder modulators have been fabricated, packaged and tested for the fiber-optic analog transmission system applications, Device performances including halfwave voltage, insertion loss, on-off ratio, and modulation frequency responses were measured, Long-term halfwave voltage stability, de-bias voltage stability, and optical power handling capability at 1.3-mu m wavelength were investigated, A carrier-to-noise ratio of 53 dB and 80-channel television transmission have been demonstrated using the packaged polymer modulators.