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Internet Signal Strength in dBmv

New Poster

Internet Signal Strength in dBmv

How can I determine Internet Signal Strength in dBmv, at the modem, and if possible, at the house cable input?

Diamond Problem Solver

Re: Internet Signal Strength in dBmv

Signal strength isn’t really measuring internet speed, db is measuring the signal to the modem for it to work. Use a speed test to measure internet speed.
https://forums.xfinity.com/t5/Your-Home-Network/Video-10-things-you-can-do-right-now-to-fix-your-int...

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Expert

Re: Internet Signal Strength in dBmv

Didn't really see the OP inquire / reference about speed problems. What problems are you having exactly ? What modem do you have ? Is it supplied by Comcast ?


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New Poster

Re: Internet Signal Strength in dBmv

Internet speed is not issue. When the weather gets hot, or I reboot the modem, it’s takes hours for the modem to reconnect with the network. A tech informed us that our signal strength was -9dBmv with 0 +\- 15dBmv as spec range. And that signal strength form the network is likely the cause.
Expert

Re: Internet Signal Strength in dBmv

That's low / weak. What do the SNR's and the upstream power level numbers look like ? Try getting them here http://192.168.100.1 or here http://10.0.0.1

Please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.




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New Poster

Re: Internet Signal Strength in dBmv

Thanks for helping. 

 

Downstream Power Level (if I'm reading the right feature) ranges between -8.6 and -11.8 (1-32 increasingly smaller values, plus a value labeled '159' which is -11.7dBmV.

 

Upstream power level is 41.5 dBmV.

 

We've never had issues with signal levels before.  I'm looking to troubleshoot and understand before I engage tech support.  I'm assuming these signal levels are at the modem, any way to determine these values at the source (house input), without buying an expensive piece of monitoring gear?

----------------------------------------------------------------

Here are the Modem particulars, if needed:

HW Version:2.2

Vendor:Technicolor
BOOT Version:S1TC-3.49.18.14
Core Version:1.0
Model:CGM4140COM
Product Type:XB6
Flash Part:8192 MB
Download Version:Prod_18.1_d31 & Prod_18.1
Serial Number:152930069116313012
----------------------------------------------------------------
Expert

Re: Internet Signal Strength in dBmv

As stated, it is weak. Upstream is o/k. The SNR's ?



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New Poster

Re: Internet Signal Strength in dBmv

Sorry for the delayed response.

 

Downstream SNR ranges from 41.7 to 38.5  (those 32 readings), plus the column labeled 159 is 14.4 dB.

 

Power levels tonight range from -8.6 to -11.7.

 

Thanks for your continued assist!

 

Randy

Official Employee

Re: Internet Signal Strength in dBmv

Greetings, rp316! I appreciate you taking the time to reach out to us here on the forums. I hope you are having an amazing day. I apologize to hear you are running into issues with your internet connection. That's certainly frustrating. I would like to look further into this. Can you please send me a PM with your first and last name so I may further assist you?

 

To send a private message, please click my name "ComcastMichael" then select "Send a Message" on the right side.


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Expert

Re: Internet Signal Strength in dBmv

The SNR's are o/k FWIW. The 14.9 on the 159 on the DOCSIS 3.1 / OFDM channel is a firmware glitch and is not accurate. I'm out now.... Good luck with it ! Smiley Happy



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Official Employee

Re: Internet Signal Strength in dBmv

Hello, rp316. I have not heard back from you. If you still need assistance, please feel free to start a new public thread.


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