50M : What can cause this intermittent power level fault

[mikep]

It all started on Wednesday morning after very bad rainfall, and apparently there was an area fault. But I think it is still happening.

It starts at 8am, and goes up and down all the time, eventually it is back alright on the evening. I have an engineer booked as I called about my Tivo box problems (channels are breaking up). The tech support department does not know if work is happening in my area (Teesside).
On Wednesday the cable modem tech support didnt even want to know about my powerlevels at -14.x with a SNR at 30.0. But the UK Tivo team did.

Downstream 09:16 06/04/2012 - Normal

Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power SNR Docsis/EuroDocsis locked
Locked QAM256 204 55616000 Kbits/sec 315000000 Hz 2.8 dBmV 40.6 dB Hybrid
Locked QAM256 201 55616000 Kbits/sec 291000000 Hz 3.3 dBmV 40.9 dB Hybrid
Locked QAM256 202 55616000 Kbits/sec 299000000 Hz 3.5 dBmV 41.4 dB Hybrid
Locked QAM256 203 55616000 Kbits/sec 307000000 Hz 3.2 dBmV 40.9 dB Hybrid

Downstream 09:47 06/04/2012 - BAD

Downstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power SNR Docsis/EuroDocsis locked
Locked QAM256 204 55616000 Kbits/sec 315000000 Hz -13.7 dBmV 29.3 dB Hybrid
Locked QAM256 201 55616000 Kbits/sec 291000000 Hz -14.1 dBmV 28.9 dB Hybrid
Locked QAM256 202 55616000 Kbits/sec 299000000 Hz -13.8 dBmV 29.3 dB Hybrid
Locked QAM256 203 55616000 Kbits/sec 307000000 Hz -13.7 dBmV 29.4 dB Hybrid

Downstream 10:01 06/04/2012

Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power SNR Docsis/EuroDocsis locked
Locked QAM256 204 55616000 Kbits/sec 315000000 Hz 3.1 dBmV 40.9 dB Hybrid
Locked QAM256 201 55616000 Kbits/sec 291000000 Hz 3.6 dBmV 41.4 dB Hybrid
Locked QAM256 202 55616000 Kbits/sec 299000000 Hz 3.9 dBmV 41.8 dB Hybrid
Locked QAM256 203 55616000 Kbits/sec 307000000 Hz 3.6 dBmV 41.1 dB Hybrid

Upstream is constant at:

Upstream Channels
Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power
Locked ATDMA 2 20480 Kbits/sec 35800000 Hz 46.0 dBmV

[General Maximus]

weird, both the power and snr are way too low, I am curious to see what is causing it unless some water got into the cabinet or something. How often does it happen and is it back to normal now?

[mikep]

It's been happening since wednesday between 8-10am after the 10am its fine, apart from Wednesday night, when it was pouring down with very bad rain. There was an area fault that has been cleared since. The cable modem support team in india wasn't interested.

I have a feeling its an area fault or repair work going on other cabinents. But the support team in india was useless and I only had luck speaking to the uk tivo based team. ( as i lose my on demand and some channels when it happens).

[General Maximus]

maybe they are doing the upgrades in your area for the speed doubling

[mikep]

Another morning 7am: it has been raining outside.


Downstream 07:03 07/04/2012

Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power SNR Docsis/EuroDocsis locked
Locked QAM256 204 55616000 Kbits/sec 315000000 Hz -13.5 dBmV 29.5 dB Hybrid
Locked QAM256 201 55616000 Kbits/sec 291000000 Hz -13.7 dBmV 29.0 dB Hybrid
Locked QAM256 202 55616000 Kbits/sec 299000000 Hz -13.5 dBmV 29.5 dB Hybrid
Locked QAM256 203 55616000 Kbits/sec 307000000 Hz -13.4 dBmV 29.5 dB Hybrid

So its a fault either when it rains or they doing work on a saturday morning.

---------- Post added at 08:36 ---------- Previous post was at 07:05 ----------

And back working again its like clockworkish



Downstream 07:48 07/04/2012

Lock Status Modulation Channel ID Max Raw Bit Rate Frequency Power SNR Docsis/EuroDocsis locked
Locked QAM256 204 55616000 Kbits/sec 315000000 Hz 3.3 dBmV 40.9 dB Hybrid
Locked QAM256 201 55616000 Kbits/sec 291000000 Hz 3.8 dBmV 41.3 dB Hybrid
Locked QAM256 202 55616000 Kbits/sec 299000000 Hz 3.9 dBmV 41.8 dB Hybrid
Locked QAM256 203 55616000 Kbits/sec 307000000 Hz 3.7 dBmV 41.4 dB Hybrid

[jb66]

The networks fairly waterproof, probably a faulty amp or attenuator in the amp

[mikep]

Thanks jb66 I will mention this to the technician on Tuesday.

[Sephiroth]

Yeah right JB. In my area, the drop points are where water collects through ground level wear and tear. Plus the outside wall box is a candidate.

But the puzzle on this one is that upstream isn't attenuated. So an amplifier is a reasonable bet.

Or a duff SH (unlikely).

[jb66]

When water gets into a splitter the high frequencies drop and don't recover, it has to be swapped out, as it's coming back I don't think it's water related. One area I work in the taps are actually underwater everytime it rains and it doesnt have the effect it has above

[mikep]

Thanks for the response Sephiroth, and other people (I forgot to thank General Maximus - sorry!) , who responded to the thread. I dont think its the SuperHub, As i can lose the internet connection on both my tivo boxes. Also certain channels become garbled on the tivo box.

I am noticing VM superhubs wireless devices are offline in my area on the morning, (but they could turning off their broadband connections).

The greenbox outside can be a bit lose, and I think rain might have got in it on Wednesday early AM, as it was practically raining sideways and in the direction of the greenbox door.

I just want an idea what is happening so I can arm myself with thoughts for the technician coming on Tuesday.

[mikep]

Its alright this morning no garbled channels, power levels are fine. The weather is ok outside. Still sounds like a faulty amp or attenuator? Its weird on how its fine on a Easter Sunday when I think they be no "work" going on with the networks?

[jb66]

Hopefully when the amp is going offline its flagging as an outage and is fixed

[General Maximus]

does the system automatically detect that and report it or is it a case of customers ringing up and moaning?

[Sephiroth]

The street cabinet equipment is passive. So the only way it can be monitored is via active devices; namely optical nodes and STBs/modems.

As I've mentioned a few times before "Project Storm" collects data from all active devices on the network every hour, posting tens of millions of records per day. Or at least they introduced Automun 201; whether or not they're still doing it, I don't know.

By the number of times people have to call an engineer, it doesn't seem to be being used properly or at all.

[jb66]

I think if 100s of mac addresses go offline it can be traced but cant say for sure as I've not seen that side of the business