| 摘要 |
In a broadband communications system whose subscriber lines are preferably formed by optical waveguides, via which TV broadband signals are transmitted as pulse-modulated signals, each TV programme (P1) is fed for TV programme distribution in a plurality of time slots to programme-specific inputs (e11...e14) on time slot-specific switching levels (ZE1) of a broadband switching arrangement whose switching point switches (11kt...p4kt) are provided on the output side with emitter follower circuits. When the actual power switches of the switching point switches (...p1kt) are in the blocking condition, their emitter follower circuits are also blocked, in order to increase the stop-band attenuation and suppress crosstalk, by a time-modulated (PPM-)signal pulse through-connected via a closed switching point switch (11kt); when the switching point switch (p1kt) is blocked, the broadband signal concerned is then subjected to the cascaded stop-band attenuation of the power switch and emitter follower. The switching point switches and threshold value multiplex circuits are preferably formed by logic elements implemented using ECL technology. <IMAGE>
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