CTC Union EOC-20, Руководство пользователя

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10.4.2 Isolator
An Isolator is required at the entrance point to the apartment (the root of the coax distribution tree).
The Isolator serves 2 purposes:
To block the EoCNA signal from spreading outside the apartment to avoid security and privacy
issues.
To reduce the isolation between splitter outputs and thus increase the connectivity coverage
between stations connected to the network. The isolator introduces mismatched impedance at
the splitter's input which causes the isolation between outputs to be reduced by about 10dB or
more. The mismatching is done only in the EoCNA band and is effective only for the splitter
topology.
There are some installations where the apartment uses two ports of an outdoor tap (or splitter), as
seen in Figure 1. In this case, installation should be as in Figure 2 and an isolator and a 1:2 splitter
should be added between the tap port and the apartment. Note that the 1:2 splitter in this installation
reduces the Coax video signal by about 3dB.
a.) Recommend using TAP to install EoCNA modem.
10.5. Physical Connection
The examples in Figure 2 are given for a CATV signal in the network.
10.5.1. MUX Access over Coax Cables
Application Name: MUX access on coax cables
HW Configuration: Coax
Physical Interface:
Coax
Transmission Power
[dBm] 8 +/- 1dbm
Dynamic Range [dB]: (see
Table 1
)
Collision detection:
Disabled
MAC mode: Synchronous
Transmission Mask Type:
Flat
CATV to EoCNA Insertion
Loss[Master]: 0.5 dB +- 0.5dB
EoCNA to TV Insertion
Loss[CPE]: 0.5 dB +- 0.5dB
Table 2: Specifications of MUX access over coax application