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Uplink light blinks. No downlink and internet light.
I change to this NETGEAR AC1750 (16x4) DOCSIS 3.0 WiFi Cable Modem Router (C6300) 3 month ago. Some issue came up last night that suddently all device cannot reach out to the internet - although the Wifi was all still connected. My first try was to reboot the router from 192.168.0.1. After that the cable connection showed in progress from the page. I used my phone LTE to check for the outage but saw none - comcast actually said the service is up but there is a problem with my device. Since it was late last night I didn't do further investigation and went to sleep.
This morning things not get any better - same symptom. I called comcast and they say it looks like there is some issue with my modem, not from their side. They will send a technician tomorrow but if they find out it's due to the problem of my device they will charge me 40 bucks. Later, I plugined the TV box and connected to my TV just wish to verify if the signal can come into my house which it did. So it does look like some issue with my device.
I'm wondering why my modem suddenly start to act like this and if any one had same issue before?
Thanks in advance.
What do the modem's signal stats look like ? If you can get them, please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.
Update: so the problem might remain in mystery then... this morning everything comes back to normal - before the time technician suppose to come. I have to go to work so I cancel the appt.
I'm not sure if it's either the hardware issue or software issue. I didn't change anything in my modem/router config yesterday.
However I'm still wondering if I should change the starting frequency in the cable connection page in my modem/router? Now I set the value to 561000000 2 days ago(before was blank) and I can see now all the channel is under 561000000Hz... so if I change the value to a higher value would I find more channel?
Note that when the issue happened there was no channel can be shown in this page.
The downstream power is marginal / weak and the SNR's are out of spec. Stuff you can try if you like;
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.