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Speeds less than 0.5 Mbit on Blast Tier - Northwest Chicago

Regular Visitor

Speeds less than 0.5 Mbit on Blast Tier - Northwest Chicago

My Blast Tier connection usually gets well above the promised 100 Mbit, often 120 or more. About two weeks ago it started dropping to <0.5 Mbit download speeds. Upload is unaffected. This usually happens twice a week, after 10 PM and lasts 24 hours. No connection issues are detected on either end, so customer service won't acknowledge the problem over the phone. I suspect it may be weather-related and would like an engineer to come out and check.

 

Modem: SB6141

Router Archer C3200

 

Modem signal: https://i.imgur.com/KHUIx4y.png

 

Modem log: https://i.imgur.com/agFCuOP.png

 

For the record, I have already powered cycled both the modem and the router, connected the modem to the PC, reverted to factory settings, everything.

 

Edit: Now my connection is completely down. My cable box is also not receiving any TV guide data.


Accepted Solutions
Official Employee

Re: Speeds less than 0.5 Mbit on Blast Tier - Northwest Chicago

Glad to hear that the maintenance team  was able to resolve the issue. Post again if you need anything else. 

 

KenF


All Replies
Expert

Re: Speeds less than 0.5 Mbit on Blast Tier - Northwest Chicago

Your upstream levels are out of spec. You'll need a tech to fix that. 

 

I've asked a Comcast employee to help you. You should expect a reply in this thread. 



"Keepin' it clean since '09"
I am not a Comcast employee, just a moderator.
Expert

Re: Speeds less than 0.5 Mbit on Blast Tier - Northwest Chicago

And the SNR's are very low / out of spec. Looks like there is some noise ingress leaking into the line somewhere. That can cause random disconnects, spontaneous re-booting of the modem, and speed and latency problems. 


Some stuff that you can try if it applies;

 

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.


Official Employee

Re: Speeds less than 0.5 Mbit on Blast Tier - Northwest Chicago

AlexAllen, I can take a look at any signal issues and send a tech as necessary. Please send me a private message with your full name, address, and phone number for more help. 

 

KenF

Regular Visitor

Re: Speeds less than 0.5 Mbit on Blast Tier - Northwest Chicago

Message sent. Thanks, guys.

Official Employee

Re: Speeds less than 0.5 Mbit on Blast Tier - Northwest Chicago

Glad to hear that the maintenance team  was able to resolve the issue. Post again if you need anything else. 

 

KenF