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Separation between outputs of splitters (crosstalk attenuation) is very important parameter of the devices. It determines level of interferences coming from other branches of the network connected to the splitter. It should be as high as possible.
Usually splitters have catalog separation between 20-25 dB. It should be known that manufacturers also define (or should do) minimum separation. Due to internal construction, the separation is usually not the same between different pairs of outputs. There may be pairs for which the attenuation reaches even 50 dB. It may be utilized for separation of the most vulnerable network sections.
Below there are presented simplified block diagrams of splitters together with connector layout in typical housings. Despite the fact that practically all manufacturers use the same layout and similar internal construction, it is recommended to examine the concrete splitter before installing in the system.
Internal construction of two-way splitter
Internal construction of three-way splitter
In the case of three-way splitters there are two versions in the market. The first one is characterized by practically identical crosstalk attenuation between each pair of the splitter. The second one has much better separation between the outermost pair of connectors. The differences may vary from 7 - 8 dB/ 20 dB, to 4 dB/24 - 28 dB.
Internal construction of four-way splitter
Internal constructions of six-way splitters
Similarly to three-way splitters there are two kinds of these splitters that differ in separation between specific pairs of outputs.
Internal construction of eight-way splitter
There may be some specific solutions - the installer should always have access to specifications of the splitters used.
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