BobC_NJ's profile

Contributor

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23 Messages

Tuesday, May 26th, 2020 12:00 PM

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Upstream issues on a NETGEAR C3700

Tech came out a few weeks ago & replaced loose external connectors. We had service to was up to spec for a few days, but is getting more erratic. DSLReports gives good DL speeds, but UL speeds have been spotty. Uplink light also keeps blinking

After spending the morning trying to work from home, I chk'ed the signal etc, rebooted & chk'ed again (ouch)

UpStream2.jpgUpStream.jpg

the top one is after the modem reboot.

 

Time for new hardware here or does Comcast need another visit?

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Contributor

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23 Messages

5 years ago

Well since the powers seems to have trashed to forum, let's see if I can paste text:

 

Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 1 5120 Ksym/sec 36500000 Hz 54 dBmV
2 Not Locked Unknown 4 0 Ksym/sec 17300000 Hz 0.0 dBmV
3 Not Locked Unknown 3 0 Ksym/sec 23700000 Hz 0.0 dBmV
4 Locked ATDMA 2 5120 Ksym/sec 30100000 Hz 54 dBmV

Expert

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111.5K Messages

5 years ago

The upstream power is still too high. The numbers don't lie. Something intermittent is going on. Their is an impairment of some sort. And only 2 channels are locked in. Should be 3 to 5. Have you done any of the tips ?

Contributor

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23 Messages

5 years ago

Having done nothing:

 

 

http://www.dslreports.com/speedtest/64211777

I then get excellent results.

But still?

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 9 489000000 Hz -5.6 dBmV 41.8 dB 0 0
2 Locked QAM256 10 495000000 Hz -6.4 dBmV 42 dB 0 0
3 Locked QAM256 11 507000000 Hz -4.1 dBmV 43.1 dB 0 0
4 Locked QAM256 12 513000000 Hz -3.7 dBmV 44.6 dB 0 0
5 Locked QAM256 13 519000000 Hz -2.9 dBmV 44.6 dB 0 0
6 Locked QAM256 14 525000000 Hz -3.3 dBmV 44.6 dB 0 0
7 Locked QAM256 15 531000000 Hz -3 dBmV 44.6 dB 0 0
8 Locked QAM256 16 537000000 Hz -2.7 dBmV 44.6 dB 0 0
 
Upstream Bonded Channels (Partial Service)
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 1 5120 Ksym/sec 36500000 Hz 54 dBmV
2 Not Locked Unknown 4 0 Ksym/sec 17300000 Hz 0.0 dBmV
3 Not Locked Unknown 3 0 Ksym/sec 23700000 Hz 0.0 dBmV
4 Locked ATDMA 2 5120 Ksym/sec 30100000 Hz 54 dBmV
 

 

Expert

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111.5K Messages

5 years ago

The upstream power is too high / out of spec. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, and latency problems.

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 get the techs re-involved until it is fixed properly.  Good luck !

Contributor

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23 Messages

5 years ago

Since they are/were Comcast installed wiring, connectors etc & they claim to have removed the splitter(s), I did nothing other than a visual chk for mouse/squirrel/moose damage & found none.

Meanwhile from the twilight zone of networking:

 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 9 489000000 Hz -5.7 dBmV 43.1 dB 9 59
2 Locked QAM256 10 495000000 Hz -8.6 dBmV 40.6 dB 30 0
3 Locked QAM256 11 507000000 Hz -4.2 dBmV 43.9 dB 24 0
4 Locked QAM256 12 513000000 Hz -4.1 dBmV 44.1 dB 12 65
5 Locked QAM256 13 519000000 Hz -3.3 dBmV 44.6 dB 19 0
6 Locked QAM256 14 525000000 Hz -3.6 dBmV 44.6 dB 5 34
7 Locked QAM256 15 531000000 Hz -2.9 dBmV 44.6 dB 7 50
8 Locked QAM256 16 537000000 Hz -4.2 dBmV 43.4 dB 8 27
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 1 5120 Ksym/sec 36500000 Hz 48 dBmV
2 Locked ATDMA 4 5120 Ksym/sec 17300000 Hz 49.5 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 23700000 Hz 49.2 dBmV
4 Locked ATDMA 2 5120 Ksym/sec 30100000 Hz 49.8 dBmV
 
Extended Upstream Transmit Power
Enable Extended Upstream Transmit Power

 

Extended transmit is actually enabled, but doesn't paste as text

Contributor

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23 Messages

5 years ago

More fun today:

http://www.dslreports.com/speedtest/64240517

and

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 9 489000000 Hz -5.4 dBmV 43.1 dB 9 59
2 Locked QAM256 10 495000000 Hz -7.1 dBmV 41.9 dB 30 0
3 Locked QAM256 11 507000000 Hz -4.1 dBmV 43.6 dB 24 0
4 Locked QAM256 12 513000000 Hz -3.7 dBmV 44.5 dB 12 65
5 Locked QAM256 13 519000000 Hz -2.9 dBmV 44.6 dB 19 0
6 Locked QAM256 14 525000000 Hz -3.3 dBmV 44.6 dB 5 34
7 Locked QAM256 15 531000000 Hz -2.8 dBmV 44.5 dB 7 50
8 Locked QAM256 16 537000000 Hz -3.1 dBmV 44.5 dB 8 27
 
Upstream Bonded Channels (Partial Service)
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 1 5120 Ksym/sec 36500000 Hz 54 dBmV
2 Not Locked Unknown 4 0 Ksym/sec 17300000 Hz 0.0 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 23700000 Hz 54 dBmV
4 Locked ATDMA 2 5120 Ksym/sec 30100000 Hz 54 dBmV
 
Extended Upstream Transmit Power
Enable Extended Upstream Transmit Power
 
Current System Time:Wed May 27 08:44:37

Expert

 • 

111.5K Messages

5 years ago

You are going to need to get the techs involved.  Bear in mind that if the premises facing techs can not find or fix a problem at your home, it is they who are responsible for escalating it to their line / network / maintenance dept. techs. The problem may lie beyond your home in the local neighborhood infrastructure somewhere but it is their S.O.P. to start at the home. Good luck with it !


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