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Within the HHI Broadband Communications System, besides some digital, optical subscriber lines an analog optical subscriber line has been installed, offering as well simultaneously three color-TV-programs, one videophone channel, four stereo-broadcast programmes and additional channels for telephone and data to the subscriber. In order to make a statement about the quality of that analog optical broadband-transmission- line employed for that, extensive measurements of the signal-to-noise ratios in the TV- and stereo-broadcast channel, the signal-to-cross- modulation ratio in the frequency range of the TV-channels, the cross-talk attenuation and the harmonic ratio in the stereo-broadcast channel have been performed. Results however show, that the quality standards for national CATV-Systems cannot be achieved by this optical analog link with its load of the frequency band and with the employment of the AM-IM-modulation for TV- and videophone signals.