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Random Internet Drops?

Posted by
Frequent Visitor

Message 1 of 11
199 Views

Recently, my internet has been randomly dropping and coming back after about 3-5 min. Happens at any hour without warning. Noticed that inside my router/modem (Scientific-Atlanta DPC3941T) that the Initialization Procedure all say "Incomplete" when this happens and also only locked to 1 Channel for Upstream but I have locked to 24 for Downstream. Is this normal?

 

Attached are some files for more clarification. If anyone has any idea's what is going on or how to fix please let me know. Not sure if the modem is the problem or something else. I am thinking my Upstream levels are too high and also should be locking on to more than 1 as well?

down-up bonding.png
initial startup.png
10 REPLIES
Posted by
Frequent Visitor

Message 2 of 11
173 Views

So after splitting the coax that comes straight into the house to the UNITY splitter from comcast and using that line I get much better Upstream Channels (3) and also i get much lower Upstream power levels that I am happy with....

 

BUT that being said I get much HIGHER Downstream levels now.... over 10... which I am not happy about...? Any ideas where to go from here? 

 

Attached is the updated power levels and channels from the new splitter setup..

 

 

new.png
Posted by
Connection Expert

Message 3 of 11
157 Views

A bit over 10 dB on the downstream isn't so bad if you are not having any problems. Over 15 dB can cause the oversaturation of the front end of the modem's tuner and lead to clipping / waveform distortions.




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Posted by
Frequent Visitor

Message 4 of 11
142 Views

Still tinkering with the coax cables and now I have the main COAX from OUTSIDE split to the modem. (It is split twice since I didnt have long enough coax or an extender so I split it) Anyway, the downstream power levels are pretty good now, but now we got a spike in the Upstream power levels.

 

In short, Outside cable to spliter to upstairs to spliter to modem. So 2 spliters and no amp, etc.

 

SO, would it be better to use the UNITY splitter/amp or not?

 

Pic of levels WITHOUT splitter (straight from outside).

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Posted by
Connection Expert

Message 5 of 11
138 Views

Put it back to the last way that you had it. It is better than this way.




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Posted by
Frequent Visitor

Message 6 of 11
130 Views

I would however I am unable to since the modem would have to stay in my basement and would have to rewire all my ethernet cables since all my desktops, xbox, etc are all hard wired from the rooms upstairs.

 

Is there any way to lower the upstream any other way? I am gonna order a coax barrel connector to replace the one splitter, but not sure how much 1 splitter will reduce the level?

Posted by
Connection Expert

Message 7 of 11
119 Views

Every reduction in unneeded splitting helps. If you are eliminating a 3.5 dB splitter port, the upstream will be reduced by the same amount and the downstream will be increased by the same amount. They work opposite of each other. It's a balancing act.

 

The preferred coax config is to have 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. 




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Posted by
Frequent Visitor

Message 8 of 11
112 Views

Gotcha, gonna try to get a barrel connector and see how it drops the upstream. So is it best to bypass the UNITY splitter/amp thing and go straight from the pole to splitter to modem? or should I go UNITY splitter to modem? Not sure whats best?

Posted by
Connection Expert

Message 9 of 11
106 Views

It depends. What yields the best results is what's "best". Good luck !




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Posted by
Frequent Visitor

Message 10 of 11
103 Views

Thanks for the help!

Posted by
Connection Expert

Message 11 of 11
99 Views

Smiley Happy




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