Installation Guide

Table Of Contents
Optional Modules
78-4002497-01 Rev F 7
Optional Modules
The tap accepts several types of modules that define specific tap functions.
Directional Coupler (DC)
The plug-in directional coupler (DC) module sets the tap value. The orientation of
the DC determines the RF flow through the tap. The DC is a plug-in module that is
installed in the field. Refer to Installing Optional Modules (on page 28) for
installation instructions. Refer to Tap Part Numbers (on page 44) for a listing of
available tap values.
Directional Coupler/Equalizer (DC/EQ)
The DC/EQ functions like a DC, but includes a fixed equalizer on its tap port that
increases loss at lower frequencies. The additional low-frequency loss forces a
greater percentage of an HFC system's auto leveling home communications
terminals (such as cable modems and addressable set-tops) to transmit their reverse
signals at desirable high levels. This improves carrier to "drop induced" ingress
ratios.
The DC/EQ can equalize the tap port from 5 MHz to 1 GHz in steps from 3 dB to 18
dB. The signal down the line is not affected. The DC/EQ is a plug-in module that
can be installed in the field. Refer to Installing Optional Modules (on page 28) for
more information.