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IBM 8265: Planning and Site Preparation Guide
WAN 2 Module E3/DS3 Coax Cables and Connectors
The media for both E3 and DS3 daughter cards is a 75 ohm impedance coaxial pair
with BNC connectors for each direction of transmission.
Cabling Information
Note: the 25 dB attenuation @ 400 MHz corresponds to an attenuation of
12 dB @ 17 MHz, assuming that follows approximately a
law.
Cabling Distances
Because the maximum recommended distance depends on the quality of cabling
used, the values given in are approximate.
Table 60. E3/DS3 Cabling Details (BNC 75 ohm)
Cable Type Impedance Attenuation @ 400 MHz
RG59 75 ohm 25 dB MAX / 100 m
Table 61. E3/DS3 Cabling Distances
I/O Card Type Cable Type Maximum Recommended Distance
E3 RG59 coax 100 m (330 ft) based on a power budget of 12 dB
@ 17 MHz.
DS3 RG59 coax 68 m (225 ft) default, 135 m (450 ft).
If cable distance exceeds 68 m (225 ft), the default
configuration setting for the port must be changed.
See the Media Module Reference Guide for details
on how to do this).
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