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Terrible Signal, Terrible Wiring, Intermittent Internet Speed

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Terrible Signal, Terrible Wiring, Intermittent Internet Speed

I am subscribed to Xfinity Triple Play (TV, Internet, Voice) which includes Blast! with speeds of 105Mbps. 

 

I am getting nowhere near that speed with peak being 34 down and 12 up on a good day. Usually I'm stuck at 3Mbps down with my upload still at 12.

 

I've had techs come out and run new wire from the ground block, put an amp in, and upgrade the ALL my devices. When I talk to support, they recommend power cycling everything or they  send a "refresh signal."

 

The Router / Modem / VoIP is a Cisco DPC3941T provided by Comcast.

 

Speeds from a direct connection are as follows;

 

(XFINITY Speed Test)

Test 1: 34.23Mbps Download, 12.13Mbps Upload.

Test 2: 24.22Mbps Download, 11.99Mbps Upload.

IPv6 shows slower speeds at 6.49Mbps down, 11.84Mbps up.

 

Signal Status (Simplified status page so it would fit):

1zh3dll.jpg

 

SNR on channel 2 is usually poor at 16dB.

 

This is the wiring job a technician did.

 

IMG_20160726_151142_1IMG_20160726_151131_1IMG_20160726_151305_1IMG_20160726_151441_1

 

Any help is appreciated. 

Expert

Re: Terrible Signal, Terrible Wiring, Intermittent Internet Speed

The downstream power levels are weak. The SNR's are out of spec on some of the channels. And the upstream power is almost out of spec as well. It may indeed be fluctuating farther out of spec intermittently. You need to get them back out there until they fix it right.



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Frequent Visitor

Re: Terrible Signal, Terrible Wiring, Intermittent Internet Speed

Update: I have installed new coax to replace the older RG-59 with RG-6, installed 75ohm caps, and installed a new ground block outside since the current one was showing age.

 

Speeds are holding steady at 105+Mbps down. Downstream and upstream levels are now in the acceptable levels, and TV does not cut out as it did before.

 

I think I've fixed the problem, I'll post an update in a day or so.

Expert

Re: Terrible Signal, Terrible Wiring, Intermittent Internet Speed

For curiosity, what do the signal stat figures look like now ?



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Expert

Re: Terrible Signal, Terrible Wiring, Intermittent Internet Speed

You should also reduce the severity of this coax bend (if you haven't already) behind the modem.

 

Terrible Signal  Terrible Wiring  Intermittent Int...   Comcast Help and Support Forums.png

 



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Frequent Visitor

Re: Terrible Signal, Terrible Wiring, Intermittent Internet Speed

Well, the issue still exists. Downstream channel 2 has no lock and has an SNR of 5.438 dB. All the other channels are fine. What could be the issue?

Expert

Re: Terrible Signal, Terrible Wiring, Intermittent Internet Speed

I mentioned, and you know what the "issue" is. There is a signal problem. As I also stated, get them back out there until they fix it right.


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Frequent Visitor

Re: Terrible Signal, Terrible Wiring, Intermittent Internet Speed

This is the new signal stats for the modem I had before they replaced it. Just reinstalled it:

 

Untitle1d.png

Frequent Visitor

Re: Terrible Signal, Terrible Wiring, Intermittent Internet Speed

Had a senior tech come out, problem was fixed. Bad tap. 

 

Here are the new levels:

 

Untitled.png

 

 

Expert

Re: Terrible Signal, Terrible Wiring, Intermittent Internet Speed

There ya' go. Happy surfing !



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