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High Upstream Power and Low Downstream Power Again

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New Poster

High Upstream Power and Low Downstream Power Again

 

Okay so after 25 hours of troubleshooting and ruling my equipment and the computer using the connection. After cheking the router I got nothing. Checked the modem and the Netgear cm700 Needs a  downstream of -7 to +7 and an up of 38 to 48. My current is Downstream is -10.7 dBmV on 315000000 Hz so i tried 201000000 Hz and that is -8.9 dBmV. My upstream is 54 on 21200000 Hz.

 

Total Uncorrectable Codewords is high and growing.

Can only get about 10 Mbps on speed test this morning since it's realy bad, but should get around 100 Mbps.

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Expert

Re: High Upstream Power and Low Downstream Power Again

What are the power levels for all the channels shown?

If there are any splitters that you could temporarily bypass, bypass them.

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New Poster

Re: High Upstream Power and Low Downstream Power Again

I dont have any splitters on the line. I am unsure if there are any coming from the box. I know that my neighbor said that there are 2 3x splitters in the box. It is an apartment complex I assumed that was how it works. 

 

Downstream Bonded Channels (Partial Service)
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables UnCorrectables
1 Locked QAM 256 1 201000000 Hz -10.4 dBmV 36.6 dB 1562 620
2 Locked QAM 256 2 207000000 Hz -11.4 dBmV 35.5 dB 774 472
3 Locked QAM 256 4 219000000 Hz -10.7 dBmV 35.5 dB 652 180
4 Locked QAM 256 5 225000000 Hz -10.0 dBmV 35.7 dB 1321 2014
5 Locked QAM 256 6 231000000 Hz -11.0 dBmV 35.5 dB 39859 164
6 Locked QAM 256 7 237000000 Hz -10.7 dBmV 35.0 dB 16036 260
7 Locked QAM 256 8 243000000 Hz -11.0 dBmV 34.9 dB 5216 383
8 Locked QAM 256 9 249000000 Hz -12.0 dBmV 34.4 dB 2416 2194
9 Locked QAM 256 10 255000000 Hz -11.2 dBmV 35.4 dB 814 193
10 Locked QAM 256 11 261000000 Hz -12.0 dBmV 34.9 dB 9441 227
11 Locked QAM 256 12 267000000 Hz -11.5 dBmV 35.7 dB 504 275
12 Locked QAM 256 13 273000000 Hz -12.5 dBmV 35.7 dB 1266 158
13 Locked QAM 256 14 279000000 Hz -11.0 dBmV 36.3 dB 800 141
14 Locked QAM 256 15 285000000 Hz -12.2 dBmV 36.3 dB 162 113
15 Locked QAM 256 16 291000000 Hz -11.2 dBmV 36.6 dB 162 124
16 Locked QAM 256 17 297000000 Hz -11.5 dBmV 36.3 dB 197 64
17 Locked QAM 256 18 303000000 Hz -11.2 dBmV 36.3 dB 219 96
18 Locked QAM 256 19 309000000 Hz -11.5 dBmV 37.3 dB 172 121
19 Locked QAM 256 20 315000000 Hz -11.5 dBmV 36.6 dB 227 147
20 Locked QAM 256 21 321000000 Hz -11.0 dBmV 36.6 dB 243 115
21 Locked QAM 256 22 327000000 Hz -12.5 dBmV 36.6 dB 413 160
22 Locked QAM 256 23 333000000 Hz -11.5 dBmV 36.6 dB 4451 128
23 Locked QAM 256 24 339000000 Hz -12.4 dBmV 35.7 dB 5800 82
24 Locked QAM 256 25 345000000 Hz -12.0 dBmV 36.2 dB 281 78
25 Locked QAM 256 26 351000000 Hz -12.7 dBmV 36.2 dB 198 126
26 Locked QAM 256 27 357000000 Hz -11.9 dBmV 36.6 dB 243 76
27 Locked QAM 256 28 363000000 Hz -12.7 dBmV 36.2 dB 158 43
28 Locked QAM 256 29 369000000 Hz -12.5 dBmV 36.4 dB 68 43
29 Locked QAM 256 30 375000000 Hz -12.0 dBmV 36.9 dB 87 26
30 Locked QAM 256 31 381000000 Hz -12.5 dBmV 36.9 dB 61 35
31 Locked QAM 256 32 387000000 Hz -12.4 dBmV 36.6 dB 100 32
32 Not Locked N/A N/A 0 Hz 0.0 dBmV 0.0 dB 0 0

Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 3 5120 Ksym/sec 21200000 Hz 54.0 dBmV
2 Locked ATDMA 2 5120 Ksym/sec 27600000 Hz 54.0 dBmV
3 Locked ATDMA 1 5120 Ksym/sec 34000000 Hz 54.0 dBmV
4 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV
5 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV
6 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV
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Expert

Re: High Upstream Power and Low Downstream Power Again

The power levels are all out of spec.

 

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: High Upstream Power and Low Downstream Power Again

I did that ealier today. I checked the box on the side of the aparment building and the lock is not there. It has 2 three way splitters before it even starts coming my way. 

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Diamond Problem Solver

Re: High Upstream Power and Low Downstream Power Again

What probably happened (and it happens a lot in apartment buildings ), a tech moved/installed another line and moved yours further down the chain. You’ll need another tech

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