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My brand new Netgear C3700V2 randomly loses its connection

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My brand new Netgear C3700V2 randomly loses its connection

Hi all,

 

I just set up my internet and bought a brand new Netgear C3700V2 modem. After 3 days of activation, my modem started losing its connection randomly (about 4 times a day), I got to restart it to get connected. Tried to text an agent and he did a re-sync, the connection kept stable for two days and today it lost connection again. I restarted it again. Talked to an agent who insisted it was the modem. I did see the current firmware (V1.02.12) is inconsistent with what was shown on the Netgear website  (V1.02.03) but not sure if it is the reason for the connection loss. 

Is there anyone who can help me with this issue? Any idea will be much appreciated!

 

Thanks!

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Expert

Re: My brand new Netgear C3700V2 randomly loses its connection

Is this with a WiFi connection ? If so, for a test, does a computer hardwired directly to the C3700 with an ethernet cable have the same problem ?



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Re: My brand new Netgear C3700V2 randomly loses its connection

Both Wifi and ethernet connection got lost. Said it was the modem that lost its connection. Thank you!

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Expert

Re: My brand new Netgear C3700V2 randomly loses its connection

What do the modem's signal stats 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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Re: My brand new Netgear C3700V2 randomly loses its connection

Thank you! I just lost connection twice today, I called to reset modem and it's back online for now.

 

I got the Upstream power 55.5 dBmV and downstream power 2.6 dBmV, SNR 38.2 dB (I saw multiple rows, but the SNR ranges from 37.9dB to 39.4dB)

 

I checked the log, it had this critical event before disconnection, "Started Unicast Maintenance Ranging - No Response received"

 

Thank you very much!

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Expert

Re: My brand new Netgear C3700V2 randomly loses its connection

The upstream power is too high / out of spec ! That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, and latency problems.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.



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Re: My brand new Netgear C3700V2 randomly loses its connection

Thank you very much!

I do use a splitter (CISCO SE1500). I connect the modem and the splitter with an ethernet cable. I've got three desktops at home (that might be too many?) because we're all working from home now. An agent said she will call for a tech visit to our neighborhood and check the connection of the neighborhood. Is there anything I can do? I can switch some desktops to WiFi connection?

 

Thank you!

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Re: My brand new Netgear C3700V2 randomly loses its connection


@jhu321 wrote:

Is there anything I can do? I can switch some desktops to WiFi connection?


That won't fix the upstream power level issue.

 

And the CISCO SE1500 is not a coax cable splitter. The type that I am referring to.

 



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Re: My brand new Netgear C3700V2 randomly loses its connection

I got it, I'm using an ethernet splitter then I'm not using any coax splitter.