Cisco 7246 - uBR Router Configuring page 13

Validation Tips
To verify the current value of the upstream frequency, enter the show controllers cable command
for the upstream port that you have just configured:
Troubleshooting Tips
If you are having trouble:
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Set the Upstream Input Power Level
The Cisco uBR7246 controls the output power levels of the cable modems to meet the desired
upstream input power level. The default setting of 0 dBmV is the optimal setting for the upstream
power level.
Caution
transmit power level. This might cause an increase in the carrier-to-noise ratio (CNR) on the network. Be
careful if you adjust this parameter. You might violate the upstream return laser design parameters.
To set the upstream input power level, use the following command in cable interface configuration
mode:
Command
cable upstream port power-level dbmv
router# show controllers cable 6/0 u0
Cable6/0 Upstream 0 is up
Frequency 7.008 MHz, Channel Width 1.6 MHz, QPSK Symbol Rate 1.280 Msps
Nominal Input Power Level 0 dBmV, Tx Timing Offset 0
Ranging Backoff Start 0, Ranging Backoff End 4, Tx Backoff Start 0
Tx Backoff End 4, Modulation Profile Group 1
part_id=0x3136, rev_id=0x02, rev2_id=0x61
nb_agc_thr=0x0100, nb_agc_nom=0x3000
Range Load Reg Size=0x58
Request Load Reg Size=0x0C
Minislot Size in number of Timebase Ticks is = 8
Minislot Size in Symbols =64
Minislot Size in Bytes = 16
UCD Count = 361894
DES Reg #580 = E204301, #584 = 3E030303, #588 = 0.
#590 = C0C0C0C.
Make sure the cable connections are not loose or disconnected.
Make sure the cable modem card is firmly seated in its Cisco uBR7246 chassis slot.
Make sure that you have entered the correct slot and port numbers when you typed the command.
Make sure that you have entered the correct upstream port number. Currently this is always u0.
Make sure you have selected a valid frequency for your headend.
If you increase the input power level, the cable modems on your HFC network will increase their
Purpose
Enter the upstream power level in dBmV.
Configuring Cisco uBR7246 Universal Broadband Router Features VC-145
Set the Upstream Input Power Level