scope:

This part of IEC 60728 lays down the measuring methods, performance requirements and data publication requirements for active wideband equipment of cable networks for television signals, sound signals and interactive services. This standard - applies to all broadband amplifiers used in cable networks; - covers the frequency range 5 MHz to 3 000 MHz; NOTE The upper limit of 3 000 MHz is an example, but not a strict value. The frequency range, or ranges, over which the equipment is specified, should be published. - applies to one-way and two-way equipment; - lays down the basic methods of measurement of the operational characteristics of the active equipment in order to assess the performance of this equipment; - identifies the performance specifications to be published by the manufacturers; - states the minimum performance requirements of certain parameters. Amplifiers are divided into the following two quality levels: Grade 1: amplifiers typically intended to be cascaded; Grade 2: amplifiers for use typically within an apartment block, or within a single residence, to feed a few outlets. Practical experience has shown that these types meet most of the technical requirements necessary for supplying a minimum signal quality to the subscribers. This classification is not a requirement but is provided to users and manufacturers for information about minimum quality criteria of the material required to install networks of different sizes. The system operator has to select appropriate material to meet the minimum signal quality at the subscriber's outlet, and to optimise cost/performance, taking into account the size of the network and local circumstances. All requirements and published data are understood as guaranteed values within the specified frequency range and in well-matched conditions.