SBG6900-AC (v1.5.x): Cable Signal Levels

Checking Signal Levels

1. Launch a Firefox or Safari browser.  Enter http://192.168.0.1 into the address box, and press the Enter key.  
   
   NOTE: A browser message on Chrome, Edge, Firefox, and Opera, may appear when accessing the Web Manager.  The message includes 192.168.01 uses an unsupported protocol and ERR_SSL_VERSION_OR_CIPHER_MISMATCH.  The Web Manager uses an earlier version of the TLS protocol and does not match the version allowed by the web browser.  Safari browsers on Apple PC and mobile devices are not impacted.  The workaround to access the Web Manager with a PC is to use the Firefox browser and set the TLS version to 1.  For workaround instructions refer to article # 19435 - 192.168.0.1 uses an unsupported protocol.
    
2. 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 # 18181 - Alert Message for Web Manager Access.
    
3. On the Login page, enter admin or a customized username in the Username field.
    
4. Enter password or a customized password in the Password field.
   
   NOTE: On later versions of the SBG6900-AC, the Wi-Fi Security Key is used as the default admin password printed on the bottom while label.  For assistance with Web Manager Access, refer to article # 18753 – SBG6900-AC: Web Manager Access.
   
   
    
5. Click the Login button.  The Home page will appear.
   
   
    
6. Move the mouse cursor over Status on the main menu, and click the Connection link on the sub-menu.  The Status - Connection page will appear.
    
7. In the Downstream Bonded Channels section, verify Power levels are within the acceptable range of - 15 dBmV to + 15 dBmV for each downstream channel. 
   
   
    
8. In the Downstream Bonded Channels section, identify the Modulation and Power to find verify SNR levels are within the acceptable range for each downstream channel. 
   
   Acceptable SNR Levels (dB): 
   If QAM64, SNR should be 23.5 dB or greater. 
   If QAM256 and DPL( -6 dBmV to +15 dBmV) SNR should be 30 dB or greater. 
   If QAM256 and DPL(-15 dBmV to -6 dBmV) SNR should be 33 dB or greater.   
   
   
    
9. In the Upstream Bonded Channels section, identify the number of Channels, Type, and Symbolic Rate to find verify Upstream Power levels are within the acceptable range for each upstream channel. 
   
   Acceptable Upstream Power Levels (dBmV):
   
   
    

   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

10. 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. 
     
11. Contact the cable provider to adjust the signal level to the acceptable level range.