Chapter 8: Downstream Cable Access Modules (DCAMs)
STANDARD Revision 1.0
C4® CMTS Release 8.3 User Guide
© 2016 ARRIS Enterprises LLC. All Rights Reserved.
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CAUTION: Changing the modulation of any channel can be service affecting to all channels associated with the same 16D
or XD CAM connector.
Power
All downstream channels associated with a given RF connector must have the same power setting. If a single channel is
configured to an RF connector, it can be configured for output power in the range of 41-60 dBmV for the XD CAM or 44-60
dBmV for the 16D CAM. If other channels are configured to that connector, the allowed maximum power level decreases
with each additional channel regardless of the administrative states of the added channels. See the table found in
Assigning a DS Channel Frequency outside the 80MHz Range for Its Connector
1.
Choose one of the associated frequencies to be the first one to change to the new frequency outside the 80 MHz
range.
2.
Set the admin state of the other associated downstream channels on that RF connector to down.
3.
Reassign those admin down DS channels to a frequency of 0 MHz.
4.
A 16D channel must be administratively down in order to set the frequency to zero. The 0 Hz frequency acts as an
enabler: it does not violate the 80 MHz constraint.
5.
Reassign the only DS channel that is in the admin up state to the desired frequency.
6.
Assign new frequencies to the DS channels that you set to the admin down state. The new frequencies must all be
within the 80 MHz edge-to-edge range and must not overlap.
7.
Bring up the other channels that are admin down.
The channel frequencies assigned to the channels of the four RF connectors are not required to be in any order. The
channel frequencies associated with RF connector DS2, for example, can be lower than those of DS0 and higher than
those of DS3.
The downstream frequency step size is 125 KHz.
The default downstream frequencyis 0 Hz.
