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Downstream Channels Not Connecting

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New Poster

Downstream Channels Not Connecting

I have been having intermediate connection issues. Some days all channels connect and some days only some. When all channels connect I recieve the 200mbs. When they dont its about 30mbs. Here is a copy of the connection, When channels arent connected. 

 

Capture.PNG

 

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Expert

Re: Downstream Channels Not Connecting

Can't see your pic. Since you are a new poster, it needs to be approved by a Forum Admin. That could take some time. In the interim, you could try hosting it at one of those free third-party pic hosting sites like Imgur or Photobucket and post the link to it here.



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Re: Downstream Channels Not Connecting

1 Locked QAM256 33 627000000 Hz -7 dBmV 36.7 dB 25064 1823
2 Locked QAM256 17 531000000 Hz -4 dBmV 36.5 dB 4455 1501
3 Not Locked Unknown 18 537000000 Hz 0.0 dBmV 0.0 dB 0 0
4 Locked QAM256 19 543000000 Hz -3.9 dBmV 31 dB 1223796 898023
5 Not Locked Unknown 20 549000000 Hz 0.0 dBmV 0.0 dB 0 0
6 Not Locked Unknown 21 555000000 Hz 0.0 dBmV 0.0 dB 0 0
7 Locked QAM256 22 561000000 Hz -4.7 dBmV 38.7 dB 2411 647
8 Locked QAM256 23 567000000 Hz -5.1 dBmV 39.4 dB 2767 1097
9 Locked QAM256 24 573000000 Hz -5.5 dBmV 29.8 dB 87896020 21743166
10 Not Locked Unknown 25 579000000 Hz 0.0 dBmV 0.0 dB 0 0
11 Locked QAM256 26 585000000 Hz -5.9 dBmV 36.5 dB 332002 57797
12 Locked QAM256 27 591000000 Hz -5.8 dBmV 30.5 dB 21685416 2427150
13 Locked QAM256 28 597000000 Hz -6 dBmV 35.2 dB 39261 3439
14 Locked QAM256 29 603000000 Hz -6.3 dBmV 37.5 dB 4576 1954
15 Locked QAM256 30 609000000 Hz -6.6 dBmV 37.4 dB 4017 1337
16 Locked QAM256 31 615000000 Hz -7.1 dBmV 36.9 dB 4514 2188
17 Locked QAM256 32 621000000 Hz -7.2 dBmV 35.9 dB 0 0
18 Locked QAM256 34 633000000 Hz -7.3 dBmV 37.2 dB 0 0
19 Locked QAM256 35 639000000 Hz -7.5 dBmV 37.5 dB 0 0
20 Locked QAM256 36 645000000 Hz -7.8 dBmV 37.5 dB 0 0
21 Locked QAM256 37 651000000 Hz -8 dBmV 37.2 dB 0 0
22 Locked QAM256 38 657000000 Hz -7.8 dBmV 37.1 dB 0 0
23 Locked QAM256 39 663000000 Hz -8.1 dBmV 36.8 dB 0 0
24 Locked QAM256 40 669000000 Hz -8.3 dBmV 36.5 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 1 5120 Ksym/sec 35800000 Hz 47.5 dBmV
2 Locked ATDMA 2 5120 Ksym/sec 29400000 Hz 48.5 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 23000000 Hz 49 dBmV
4 Locked ATDMA 4 5120 Ksym/sec 16600000 Hz 49.5 dBmV
5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
 
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Expert

Re: Downstream Channels Not Connecting

You've got some weak downstream channel power levels and some of the SNR's are out of spec. And the upstream power is on the high side and it may be intermittently fluctuating even higher to out of spec levels. 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 book a tech visit to investigate and correct.



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New Poster

Re: Downstream Channels Not Connecting

Thanks I really appreciate it. I have only one two way splitter in the house. I changed it to a different one but it is a little older. The list seemed a little better. Do you think with a newer splitter it could be corrected?

 

1 Locked QAM256 33 627000000 Hz -6 dBmV 38.2 dB 0 0
2 Locked QAM256 17 531000000 Hz -3.4 dBmV 37.6 dB 0 0
3 Not Locked Unknown 18 537000000 Hz 0.0 dBmV 0.0 dB 0 0
4 Locked QAM256 19 543000000 Hz -3.2 dBmV 34.1 dB 20444 5750
5 Locked QAM256 20 549000000 Hz -3.1 dBmV 31.1 dB 66263 514
6 Locked QAM256 21 555000000 Hz -3.5 dBmV 33.8 dB 11209 4155
7 Locked QAM256 22 561000000 Hz -3.6 dBmV 39.5 dB 0 0
8 Locked QAM256 23 567000000 Hz -3.9 dBmV 40.2 dB 0 0
9 Locked QAM256 24 573000000 Hz -4.2 dBmV 32.6 dB 2778 0
10 Not Locked Unknown 25 579000000 Hz 0.0 dBmV 0.0 dB 0 0
11 Locked QAM256 26 585000000 Hz -4.5 dBmV 38.2 dB 0 0
12 Locked QAM256 27 591000000 Hz -4.5 dBmV 33.3 dB 0 0
13 Locked QAM256 28 597000000 Hz -4.7 dBmV 37.1 dB 0 0
14 Locked QAM256 29 603000000 Hz -5.1 dBmV 39.1 dB 0 0
15 Locked QAM256 30 609000000 Hz -5.5 dBmV 38.9 dB 0 0
16 Locked QAM256 31 615000000 Hz -6.1 dBmV 38.5 dB 0 0
17 Locked QAM256 32 621000000 Hz -6.3 dBmV 37.4 dB 0 0
18 Locked QAM256 34 633000000 Hz -6.4 dBmV 38.1 dB 0 0
19 Locked QAM256 35 639000000 Hz -6.5 dBmV 38.2 dB 0 0
20 Locked QAM256 36 645000000 Hz -6.8 dBmV 38.2 dB 0 0
21 Locked QAM256 37 651000000 Hz -6.8 dBmV 38.1 dB 0 0
22 Locked QAM256 38 657000000 Hz -6.6 dBmV 38.2 dB 0 0
23 Locked QAM256 39 663000000 Hz -6.9 dBmV 37.8 dB 0 0
24 Locked QAM256 40 669000000 Hz -7.1 dBmV 37.5 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 4 5120 Ksym/sec 16600000 Hz 48.5 dBmV
2 Locked ATDMA 1 5120 Ksym/sec 35800000 Hz 48.5 dBmV
3 Locked ATDMA 2 5120 Ksym/sec 29400000 Hz 48.5 dBmV
4 Locked ATDMA 3 5120 Ksym/sec 23000000 Hz 48.5 dBmV
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Expert

Re: Downstream Channels Not Connecting

Needs more work. You may need a tech out to investigate / correct the problem

 

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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New Poster

Re: Downstream Channels Not Connecting

ok thank you 

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Expert

Re: Downstream Channels Not Connecting

Quite welcome !



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