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WLAN Cable Access Point 6220 NTPM99CA 01 Rel 1.0 Issue 3 Dec 2004
Procedure 1-6
Checking CATV Signal and Power Level and Tuning
Action
Step Action
1. Connect an actual coaxial cable to the coaxial port on the APU.
2. Connect a measurement coaxial cable to the monitoring port on the
APU.
3. Measure the Signal Power level at monitoring port.
Note : In case of installation using a Trunk or Distribution Cable &
Connector, it is crucially recommended to measure the RF Signal level
directly at the termination of the coaxial cable from CATV AMP(TBA) or
Splitter before connecting to APU in order to ensure a perfect operation of
Cable Modem inside APU.
If the measured Signal level is outside from the allowed range referred in
DOCSIS, you should adjust the AMP Power level or perform another
proper tuning method to meet the requirement of RF signal level.
It is also recommended to measure AC voltage from CATV UPS Power
Supply to ensure a perfect operation.
Note : In case of installation using a Drop Cable, it is recommended to
measure the AC voltage from Local CATV Power Supply to ensure a
perfect operation. But if you can confirm that a power supply facility is
compliant to the power requirement of APU, this step can be skipped
4.
Check if the acquired power level converted by adding 20dBmV to
monitored value satisfy the range (-15dBmV ~ +15dBmV) referred in
DOCSIS standard. But, some level margin should be added to the
measured power level by 1 ~ 3 dB.