Jim Gurd
Premium
join:2000-07-08
Plymouth, MI
 ·Comcast
1 edit | [Connectivity] Connection intermittantly dropping
What's causing this? The connection drops and comes back repeatedly. It's usable but slow. The modem is a Motorola SB5120.
050915192627 4-Error SYNC: Hardware didn't detect SYNC msg for 600ms - Disable Upstream and trying to lock on DS
050915192625 4-Error SYNC: Hardware didn't detect SYNC msg for 600ms - Disable Upstream and trying to lock on DS
050915192619 4-Error SYNC: Hardware didn't detect SYNC msg for 600ms - Disable Upstream and trying to lock on DS
050915192617 4-Error SYNC: Hardware didn't detect SYNC msg for 600ms - Disable Upstream and trying to lock on DS
Here is my signal page:
Downstream Value
Frequency 597000000 Hz
Signal to Noise Ratio 27 dB
QAM 256
Network Access Control Object ON
Power Level -2 dBmV 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
Upstream Value
Channel ID 5
Frequency 27000000 Hz
Ranging Service ID 2902
Symbol Rate 2.560 Msym/s
Power Level 51 dBmV |
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sortofageek
Premium,Mod
join:2001-08-19
Valhalla Dr
clubs:
·Comcast
Host:
Team Helix
Distributed Comput..
Linksys
Comcast HSI
Comcast Cable TV
| I think this is it:
Signal to Noise Ratio 27 dB
»/faq/7124
If I were you, I would call Comcast tech support, tell them about the disconnects, ask them to check the modem signal levels, get a truck roll scheduled.
--
Team Helix September 2005 Roll Call - Team Helix Forum - Join Us? |
|
SparkChaser
BURY BECK
Premium
join:2000-06-06
Downingtown, PA
 ·Verizon FIOS
·Comcast
| reply to Jim Gurd
Re: [Connectivity] Connection intermittantly dropp
said by Jim Gurd  :What's causing this? The connection drops and comes back repeatedly. It's usable but slow. The modem is a Motorola SB5120. Here is my signal page: Downstream Value Frequency 597000000 Hz Signal to Noise Ratio 27 dB The testing I've done on my SB5130 shows that when the SNR gets to 27-28 things go down hill pretty fast, to where it won't even sync. Even with fairly good downstream signal levels.
Do you just have one (2to1) spltter going to your modem from the ground block? |
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Jim Gurd
Premium
join:2000-07-08
Plymouth, MI
·Comcast
| said by SparkChaser :Do you just have one (2to1) spltter going to your modem from the ground block? I just did some rearranging of splitters to see if that will improve the SNR. It's really weird. Refreshing the page gives me constantly changing results from 16dB to 38dB.
I have had essentially the same setup for 5 years with no problem until now. The trouble seemed to start after the speed upgrade. |
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Nightblade4
join:2001-12-09
Maple Park, IL
| The speed increase has brought numerous problems for peeps with old modems and peeps who are the borderline for poor levels
The 27snr level is too low to maintain a solid connection
I would like to know how the connection from the ground block to the modem is?
and what type/brand of spiltter it is? |
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SparkChaser
BURY BECK
Premium
join:2000-06-06
Downingtown, PA
·Verizon FIOS
·Comcast
| reply to Jim Gurd
Re: [Connectivity] Connection intermittantly drop
said by Jim Gurd : It's really weird. Refreshing the page gives me constantly changing results from 16dB to 38dB. Do the signals also change wildly or just the SNR? I think you're always going to see some change but yours are way off the scale. |
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Jim Gurd
Premium
join:2000-07-08
Plymouth, MI
·Comcast
| said by SparkChaser :said by Jim Gurd : It's really weird. Refreshing the page gives me constantly changing results from 16dB to 38dB. Do the signals also change wildly or just the SNR? I think you're always going to see some change but yours are way off the scale. Only the SNR seems to change. Power levels remain the same. |
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Ms_Kevlar
| reply to Jim Gurd
Re: [Connectivity] Connection intermittantly dropping
If you are using a splitter, make sure your cable modem is connected to the highest DB side of the output.
Worked for me and now I have always ON connection.
Hope this helps. |
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oldTDNickell
Premium
join:2000-12-19
Federal Way, WA | reply to Jim Gurd
Can you post your signal levels as they are now please?
»192.168.100.1/ |
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Jim Gurd
Premium
join:2000-07-08
Plymouth, MI
·Comcast
| reply to Ms_Kevlar
said by Ms_Kevlar :
If you are using a splitter, make sure your cable modem is connected to the highest DB side of the output.
Worked for me and now I have always ON connection.
Hope this helps.
I thought you want to connect it to the lowest side because the figure listed is the amount of loss caused by the splitter. I have it on the 3.5 side instead of 7. The splitter is a 5-1000Mhz version Regal brand. |
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Jim Gurd
Premium
join:2000-07-08
Plymouth, MI
·Comcast
| reply to oldTDNickell
said by oldTDNickell :Can you post your signal levels as they are now please? » 192.168.100.1/ Here goes. The SNR is fluctuating wildly but averages around 26dB. The other levels remain constant.
Frequency 597000000 Hz
Signal to Noise Ratio 26 dB
QAM 256
Network Access Control Object ON
Power Level 1 dBmV 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
Upstream Value
Channel ID 5
Frequency 27000000 Hz
Ranging Service ID 3226
Symbol Rate 2.560 Msym/s
Power Level 48 dBmV |
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oldTDNickell
Premium
join:2000-12-19
Federal Way, WA
| It could would be best to try a different model modem.
I had nothing but problems with a Moto SB5120 i was renting from comcast after the change to 256QAM.
My SNR was much better then yours at 34dB,so you are really to low.
I'll bet your having packet loss,slow web page turning and disconnect's with a SNR of 26dB.
I think it would be best to get a truck roll.
Good luck.:) |
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Jim Gurd
Premium
join:2000-07-08
Plymouth, MI
·Comcast
| said by oldTDNickell :I think it would be best to get a truck roll. Good luck.:) They're coming out Saturday. My connection has been horrible tonight. Now it seems to be better. I have no idea why. |
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oldTDNickell
Premium
join:2000-12-19
Federal Way, WA
1 edit | said by Jim Gurd :said by oldTDNickell :I think it would be best to get a truck roll. Good luck.:) They're coming out Saturday. My connection has been horrible tonight. Now it seems to be better. I have no idea why. Yes your SNR is pretty low,could be the modem or a line problem.
Good luck on the visit.:)
»/faq/7124 |
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Jim Gurd
Premium
join:2000-07-08
Plymouth, MI
·Comcast
| said by oldTDNickell :Yes your SNR is pretty low,could be the modem or a line problem. Good luck on the visit.:) » /faq/7124 Thanks.
Is it possible that it gets worse if there are more users on my node? If so the reason it may be better is people are starting to go to bed and not use their connection so I'm not sharing with as many users. Just a thought because all of a sudden things got much better. |
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oldTDNickell
Premium
join:2000-12-19
Federal Way, WA
1 edit | Have you checked to make sure all your connections are clean and tight?
This is something else i do if i have SNR problems.
It will show up here.
»/linequality |
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Jim Gurd
Premium
join:2000-07-08
Plymouth, MI
·Comcast
| reply to oldTDNickell
said by oldTDNickell :It could would be best to try a different model modem. I had nothing but problems with a Moto SB5120 i was renting from comcast after the change to 256QAM. My SNR was much better then yours at 34dB,so you are really to low. I'll bet your having packet loss,slow web page turning and disconnect's with a SNR of 26dB. I think it would be best to get a truck roll. Good luck.:) Wow!! You hit the nail on the head there. I just swapped out my SB5120 for an RCA DCM425 at my local Comcast office. My SNR is now a steady 39dB!!!
I'm going to test it out for a day or two and if things are still good I will cancel the service call. Thanks a lot for the tip about the Moto being bad. I wonder why Motorola is making such a crappy modem and I also wonder how many other people are having to swap them out. |
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Jim Gurd
Premium
join:2000-07-08
Plymouth, MI
·Comcast
| Forgot to post my speed test. It's much better than before. |
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oldTDNickell
Premium
join:2000-12-19
Federal Way, WA | reply to Jim Gurd
I'm sure you will be fine now.:) |
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