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New install with Netgear CM1200 - are signals ok?

dawalt
Regular Contributor

New install with Netgear CM1200 - are signals ok?

I just installed Comcast 1GB internet service using my own modem in a new home. The equipment is the same I used in my former home with 1GB service, a Netgear CM1200 modem.

 

The speeds seem fine so far (about 5 days so far). But today I checked the signals on the CM1200, and I saw some things I had not seen before. 

 

First on the Download channels - 3 channels have very high correctible and unocrrectible errors. Second, the power levels are all around 0 - I am used to seeing them around 3-4 dBmV. SNR looks good though. Is there any action I should take on this, are there any issues?

 

Screen Shot 2021-02-02 at 2.36.17 PM.png

Second, on the Downstream OFDM channels - power is also around 0, in my old house it's around 2.9 dBmV. Is this ok?

Screen Shot 2021-02-02 at 2.37.08 PM.png

Lastly - on the Upstream Bonded Channels, at my old house power is around 37-38 dBmV. Here, they are 51-52 dBmV. Is this ok?

Screen Shot 2021-02-02 at 2.36.48 PM.png

 

The new house is in a large city, the old house is in the suburbs. Maybe the new house is closer to Comcast equipment, so power doesn't need to be as high as the SNRs are pretty good?

 

Thanks for taking a look at this and advising me!

CCAndrew
Diamond Problem Solver

Re: New install with Netgear CM1200 - are signals ok?

You are referring to two different houses/locations, the levels won’t be the same, so it’s not a good comparison. Your upstream is high, do you have extra splitters that you can remove to lower it?

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dawalt
Regular Contributor

Re: New install with Netgear CM1200 - are signals ok?

so I guess I am asking, are the power levels that are all around 0, and th ones arounf 50 bDmV, in range? And are the 3 channels with very high errors compared to the other channels normal or should I request Comcast to look at them?

 

EDIT: Not sure why the uploaded images don't show - they did in preview. It's hard to get a constructive answer when people can't see what I am talking about.

BruceW
Gold Problem Solver

Re: New install with Netgear CM1200 - are signals ok?


@dawalt wrote: ... are the power levels that are all around 0, and th ones arounf 50 bDmV, in range? ... very high errors  ... images don't show ...

The acceptable signal ranges are given in Internet Troubleshooting Tips. 0 dBmV is ideal for downstream channels, +50 dBmV is borderline/too high for upstream channels. A few errors are normal, many errors occurring in a short period of time are problematic.

 

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