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SB6141 bad? Help with signal levels

New Poster

SB6141 bad? Help with signal levels

Hello. Recently switched back to Comcast and having trouble getting my SB6141 connecting. My older SB6121 seems to work fine, but the SB6141 won't connect.

 

Here is my SB6141 signal page:

 

Downstream Bonding Channel Value
Channel ID
Frequency 501000000 Hz 
Signal to Noise Ratio 35 dB 
Downstream Modulation QAM256 
Power Level
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
-11 dBmV 

 

Upstream Bonding Channel Value
Channel ID
Frequency 29400000 Hz 
Ranging Service ID n/a 
Symbol Rate 5.120 Msym/sec 
Power Level 55 dBmV 
Upstream Modulation [2] QPSK
[1] 32QAM
[3] 64QAM
 
Ranging Status Other 

 

Signal Stats (Codewords) Bonding Channel Value
Channel ID
Total Unerrored Codewords 2769712 
Total Correctable Codewords
Total Uncorrectable Codewords

471 

 

Highlighted
New Poster

Re: SB6141 bad? Help with signal levels

For comparison SB6121 signal (which works)

Downstream Bonding Channel Value
Channel ID 29  30  31  36 
Frequency 651000000 Hz  657000000 Hz  663000000 Hz  669000000 Hz 
Signal to Noise Ratio 34 dB  35 dB  35 dB  35 dB 
Downstream Modulation QAM256  QAM256  QAM256  QAM256 
Power Level
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
-9 dBmV   -8 dBmV   -9 dBmV   -8 dBmV  

 

Upstream Bonding Channel Value
Channel ID
Frequency 35800000 Hz  23000000 Hz  29400000 Hz 
Ranging Service ID 11046  11046  11046 
Symbol Rate 5.120 Msym/sec  5.120 Msym/sec  5.120 Msym/sec 
Power Level 49 dBmV  49 dBmV  49 dBmV 
Upstream Modulation [2] QPSK
[1] 32QAM
[3] 64QAM
 
[2] QPSK
[1] 32QAM
[3] 64QAM
 
[2] QPSK
[1] 32QAM
[3] 64QAM
 
Ranging Status Success  Retries Exceed  Retries Exceed 

 

 

Diamond Problem Solver

Re: SB6141 bad? Help with signal levels

Do you have any downstream channels? The first upstream channel is way too high and the other 3 are borderline too high? Maybe post your other modem’s levels for comparison?

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New Poster

Re: SB6141 bad? Help with signal levels

Original post is SB6141 which I am having problems with. The second post is my SB6121 which works.

 

 

Diamond Problem Solver

Re: SB6141 bad? Help with signal levels

Then obviously it’s reading too high and missing 2 upstream channels. Try resetting it?

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New Poster

Re: SB6141 bad? Help with signal levels

Actually reset it multiple times, but this time I left it go for about an hour. I finally got good levels. I think?

 

Downstream Bonding Channel Value
Channel ID 25  26  27  28  29  30  31  36 
Frequency 627000000 Hz  633000000 Hz  639000000 Hz  645000000 Hz  651000000 Hz  657000000 Hz  663000000 Hz  669000000 Hz 
Signal to Noise Ratio 36 dB  36 dB  35 dB  36 dB  35 dB  36 dB  35 dB  37 dB 
Downstream Modulation QAM256  QAM256  QAM256  QAM256  QAM256  QAM256  QAM256  QAM256 
Power Level
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
-6 dBmV   -5 dBmV   -5 dBmV   -5 dBmV   -6 dBmV   -5 dBmV   -6 dBmV   -5 dBmV  

 

Upstream Bonding Channel Value
Channel ID
Frequency 35800000 Hz  23000000 Hz  29400000 Hz 
Ranging Service ID 9339  9339  9339 
Symbol Rate 5.120 Msym/sec  5.120 Msym/sec  5.120 Msym/sec 
Power Level 46 dBmV  46 dBmV  46 dBmV 
Upstream Modulation [2] QPSK
[1] 32QAM
[3] 64QAM
 
[2] QPSK
[1] 32QAM
[3] 64QAM
 
[2] QPSK
[1] 32QAM
[3] 64QAM
 
Ranging Status Success  Retries Exceed 

Retries Exceed 

 

Diamond Problem Solver

Re: SB6141 bad? Help with signal levels

Better but you should also look at the downstream as well

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Expert

Re: SB6141 bad? Help with signal levels

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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