Spectator

Low SNR, MDD timeouts, seemed to repair itself?

I had low SNR on 10 out of 16 channels (sub 30) and was seeing MDD timeouts on my modem.

 

at times 6 channels out of 10 wouldn't even be locked. They're sending a Tech out today, but I'm worried he'll say everything is fine, because here's my current readings: (I want to make sure what happened yesterday, doesn't happen again)

ChannelLock StatusModulationChannel IDFreq. (MHz)Pwr (dBmV)SNR (dB)CorrectedUncorrected
1LockedQAM2569609.010.832.9171388366
2LockedQAM25610615.010.732.72119206325
3LockedQAM25611621.010.932.82304122319
4LockedQAM25612627.010.832.72839710451
5LockedQAM25614639.010.732.534799962114
6LockedQAM25615645.010.732.636064911136
7LockedQAM25616651.010.632.543021581274
8LockedQAM25618663.010.332.2633637221225
9LockedQAM25620675.09.931.8993396047368
10LockedQAM25623693.09.631.613908451727143
11LockedQAM25624699.09.431.516163550350431
12LockedQAM25625705.09.331.417547986769096
13LockedQAM25626711.09.631.3193356025102196
14LockedQAM25627717.09.931.2207973687136934
15LockedQAM25629729.09.531.0270315673402287
16LockedQAM25631741.09.230.8291071553554937
Total      18052758311352242

 

ChannelLock StatusChannel TypeChannel IDSymb. Rate (Ksym/sec)Freq. (MHz)Pwr (dBmV)
1LockedATDMA6512024.241.0
2LockedTDMA5256019.440.3
3LockedATDMA7512030.642.0
4LockedTDMA8256037.042.0
7 REPLIES
Established Sharer

Re: Low SNR, MDD timeouts, seemed to repair itself?

Is it something that only happened yesterday or for a longer period of time? Crews could have been doing regular maintenance.

Spectator

Re: Low SNR, MDD timeouts, seemed to repair itself?

Looks like the signals are dropping again (and I keep losing formatting on paste)

 

ChannelLock StatusModulationChannel IDFreq. (MHz)Pwr (dBmV)SNR (dB)CorrectedUncorrected
1LockedQAM2569609.011.131.33016254978
2LockedQAM25610615.011.031.237389253149
3LockedQAM25611621.011.131.240483194144
4LockedQAM25612627.011.031.149966569444
5LockedQAM25614639.010.931.061251508946
6LockedQAM25615645.010.931.0632517991002
7LockedQAM25616651.010.830.9754236202048
8LockedQAM25618663.010.430.61113827599730
9LockedQAM25620675.010.130.217442086657143
10LockedQAM25623693.09.730.0243410680214732
11LockedQAM25624699.09.529.9282688494393476
12LockedQAM25625705.09.729.8306665976534735
13LockedQAM25626711.010.029.7336425588774402
14LockedQAM25627717.010.129.63604347611022315
15LockedQAM25629729.09.629.44635923452801815
16LockedQAM25631741.09.429.34981121553735233
Total      -11599051809548392
Highlighted
Expert

Re: Low SNR, MDD timeouts, seemed to repair itself?

Looks like there's an amplifier inline... Get rid of it... Amps are bad...

 

If not Spectrum needs to come out and fix the levels... DS although slightly high, has a totally unuseable s/n.. Anything lower than 34 dB is questionable and they darn well know that modems don't work at all with channels lower than 30 dB s/n.

It is not a modem issue and I doubt adding a pad to lower the DS level will make much improvem,ent.

 This can't be fixed over the phone, needs a competent tech and probably escallation to the bucket truck guys to fix the bad line amp somewhere down the street.

Spectator

Re: Low SNR, MDD timeouts, seemed to repair itself?

They sent out the 3rd shift crew to fix their amplifier, I guess it was coming hot off the pedestal. After they fixed it, it looks like this now: 

 

  ChannelLock StatusModulationChannel IDFreq. (MHz)Pwr (dBmV)SNR (dB)CorrectedUncorrected
1LockedQAM25627717.02.640.39558786039535
2LockedQAM2569609.03.442.076723711060
3LockedQAM25610615.03.341.59606860794
4LockedQAM25616651.03.141.510999312788
5LockedQAM25619669.02.440.613478600967
6LockedQAM25620675.02.439.7286395091298
7LockedQAM25621681.02.540.5344053211562
8LockedQAM25622687.02.540.4517466094376
9LockedQAM25623693.02.640.5620412207553
10LockedQAM25624699.02.540.37381375223554
11LockedQAM25625705.02.540.38087096224357
12LockedQAM25626711.02.540.38917604239125
13LockedQAM25629729.02.440.110709551786490
14LockedQAM25630735.02.340.0123230147117887
15LockedQAM25631741.02.340.0137591000180629
16LockedQAM25632747.02.239.9149040889248221
Total      1074995971778196
Expert

Re: Low SNR, MDD timeouts, seemed to repair itself?

See if there's a reset FEC counter box... That will zero out the atrocious corrected/ uncorrected counts... to zero. But I'll bet it's fixed. S/N is now great from unuseable...

Did the tech tell you it's bad and the other crew needs to repair a street amp?

 

Spectator

Re: Low SNR, MDD timeouts, seemed to repair itself?

Yes, they checked it at the home, then at the pedestal he said, have to pass this one to line crew. I was amazed they fixed it the same night, the 3rd shift crew must have been slow.

 

He said something about reclibrating the amplifier.

 

Established Sharer

Re: Low SNR, MDD timeouts, seemed to repair itself?

Sounds like your local home service team got it right on their first trip.  The line crews are doing a huge amount of repair work on third shift in order to remove the legacy analog channels and then fix all the internet signal quality issues.