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Arris CM820 and Netgear WNDR4500 connection dropping everyday

Posted by
Connection Expert

Member Since: ‎12-24-2003
Posts: 51,231
Message 1 of 3 (2,415 Views)
Posted by
Connection Expert

Member Since: ‎12-24-2003
Posts: 51,231
Message 2 of 3 (2,414 Views)

Re: Arris CM820 and Netgear WNDR4500 connection dropping everyday




Your post was removed to a secure area out of public view because it violates forum posting guidelines.

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Tech support has been of no use to me so I am turning to where I should have in the first place.  Basically, every since I upgraded from docsis 2.0 to 3.0 this new modem drops me no less than 5 times a day and the only way to fix it is to call and have it repinged.  Sometimes troubleshooting will mention DNS othertimes it simply tells me Broadband connectivity issues.  If it is possible that I have an incorrect router setting, I beg someone to educate me so this can stop.  Also, why do I keep seeing mention to docsis 2.0 in my report below.  Admittedly, I dont understand all the data it is displaying but that seems strange.  And the mention of "uncorrectables"


I accept all opinions and you can even feel free to email me directly XXXXXXXXX.


Below is all the data I could come up with.  Feel free to ask for more.
Downstream   DCID Freq Power SNR Modulation Octets Correcteds Uncorrectables Downstream 1 28 597.00 MHz 1.89 dBmV 37.94 dB 256QAM 3330609 0 0 Downstream 2 25 579.00 MHz 2.71 dBmV 37.64 dB 256QAM 3411982 0 0 Downstream 3 26 585.00 MHz 2.29 dBmV 37.64 dB 256QAM 2982821 0 0 Downstream 4 27 591.00 MHz 2.00 dBmV 37.64 dB 256QAM 3311039 0 0 Downstream 5 29 603.00 MHz 1.86 dBmV 37.94 dB 256QAM 3554339 0 0 Downstream 6 30 609.00 MHz 1.27 dBmV 37.94 dB 256QAM 3430751 5 29 Downstream 7 31 615.00 MHz 0.72 dBmV 35.97 dB 256QAM 3454372 8 27 Downstream 8 32 621.00 MHz 0.34 dBmV 37.09 dB 256QAM 3542881 9 26 Reset FEC Counters Upstream   UCID Freq Power Channel Type Symbol Rate Modulation Upstream 1 4 34.80 MHz 51.00 dBmV DOCSIS2.0 (ATDMA) 5120 kSym/s 64QAM Upstream 4 5 27.90 MHz 51.00 dBmV DOCSIS2.0 (ATDMA) 5120 kSym/s 64QAM
 Status System Uptime: 0 d: 0 h: 13 m Computers Detected: staticCPE(0), dynamicCPE(1) CM Status: OPERATIONAL Time and Date: Wed 2013-04-17 20:32:49
 Interface ParametersInterface Name Provisioned State Speed (Mbps) MAC address LAN Enabled Up 1000(Full) 00:1D1:FE:7C:5C CABLE Enabled Up ----- 00:1D1:FE:7C:5D

Posted by
Edited on
‎04-18-2013 03:04 PM

Connection Expert

Member Since: ‎12-24-2003
Posts: 51,231
Message 3 of 3 (2,413 Views)

Re: Arris CM820 and Netgear WNDR4500 connection dropping everyday

[ Edited ]

The upstream power is borderline too high and may be intermittently fluctuating even higher out of spec.That will cause random disconnects and spontaneous re-booting of the modem.  In an effort to try to obtain better connectivity, 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 5-1000 MHz, bi-directional, and no gold colored garbage from Radio Shack, Home Depot, etc.


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 putting them back together again, then perhaps it's best to book a tech visit to investigate and correct.