SBG10: Cable Signal Levels

Checking Signal Levels

1. Launch a web browser, such as Internet Explorer, Firefox, or Safari.  Enter http://192.168.100.1 into the address box, and press the Enter key.  The Login page will appear.
   
   NOTE 1: A security or private risk alert may appear on the web browser advising users to proceed with caution when accessing the Web Manager.  There is no risk in proceeding to the Web Manager. For instructions to bypass the alert screen, refer to article 24206 - Alert Message for Web Manager Access.
   
   NOTE 2: A login page may appear to access the Web Manager.  Enter the default username admin in the Username field and enter the default password password in the Password field.  It may be required to set a unique password to proceed to the Web Manager.  For assistance with Web Manager Access, refer to article 23796 - SBG10: First Time Accessing the Status Page.
    
2. On the Login page, enter admin in the Username field.
    
3. Enter password or a customized password in the Password field, then click the Send button.  The Status page will appear. 
   
   
    
4. In the Downstream section, verify Power levels are within the acceptable range of - 15 dBmV to + 15 dBmV for each downstream channel. 
   
   
    
5. In the Downstream section, identify the Modulation and Power to verify SNR levels are within the acceptable range for each downstream channel. 
    

   Downstream Signal To Noise Ratio (SNR)
   Modulation	Power	Acceptable SNR
   64QAM	-15 to 15 dBmV	23.5 dB or greater
   256QAM	-6 to 15 dBmv	30 dB or greater
   	-15 to -6 dBmV	33 dB or greater

   
   
    
6. In the Upstream section, identify the number of Upstream Channels, Channel Type, and Symbolic Rate to verify the Power levels are within the acceptable range for each upstream channel. 
    

   Upstream Transmit Power Level
   Channel	US Channel Type	Symbol Rate	Acceptable Upstream Power Levels
   Single	TDMA	1280 Ksym/sec	45 dBmV to 61 dBmV
   	ATDMA	2560 Ksym/sec	45 dBmV to 58 dBmV
   		5120 Ksym/sec	45 dBmV to 57 dBmV
   Two	TDMA	1280 Ksym/sec	45 dBmV to 58 dBmV
   	ATDMA	2560 Ksym/sec	45 dBmV to 55 dBmV
   		5120 Ksym/sec	45 dBmV to 54 dBmV
   Three or more	TDMA	1280 Ksym/sec	45 dBmV to 55 dBmV
   	ATDMA	2560 Ksym/sec	45 dBmV to 52 dBmV
   		5120 Ksym/sec	45 dBmV to 51 dBmV

   
    
7. Refresh the page at least twice to identify variations in SNR, Downstream Power, and Upstream Power.   
   
   NOTE: If either of the signal levels is outside of the acceptable range, power cycle or factory reset the modem.  Factory resetting the modem will eliminate any customized settings.
    
8. Contact the cable provider to adjust the signal level to an acceptable range.