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Modem not working with cable splitter

Posted by
Visitor
Member Since: ‎04-25-2011
Posts: 9
Message 1 of 14 (14,166 Views)

Modem not working with cable splitter

The last couple of weeks, my modem hasn't been working consistently with a splitter. it will work for a couple of hours with the splitter. When it isn't working with the splitter, i have to connect the modem directly to the wall. After a couple of hours of being connected directly to the wall, i put the splitter in again and it will work for a couple of hours before i have to connect it directly to the wall again. I have been doing this alternating for a couple of weeks and im getting sick of it. I've tried 2 different splitters, so im pretty sure its not the splitter. Anyone know whats wrong?

13 REPLIES
Posted by
Connection Expert

Member Since: ‎06-30-2003
Posts: 7,155
Message 2 of 14 (14,160 Views)

Re: Modem not working with cable splitter

The signal must be a little off that get worst with that splitter on

please post signals from modem click this link

Posted by
Visitor
Member Since: ‎04-25-2011
Posts: 9
Message 3 of 14 (14,154 Views)

Re: Modem not working with cable splitter

I'm not sure which one im supposed to post. Downstream or upstream?

Posted by
Cable Expert

Member Since: ‎03-02-2007
Posts: 16,273
Message 4 of 14 (14,152 Views)

Re: Modem not working with cable splitter

Please post

 

downstream power level

downstream signan to noise (SNR)

upstream power level

Posted by
Visitor
Member Since: ‎04-25-2011
Posts: 9
Message 5 of 14 (14,149 Views)

Re: Modem not working with cable splitter

This is with the splitter

 

Downstream Receive Power Level : -10.5 dBmV

Downstream SNR : 36.9 dB

Upstream transmit Power Level : 54.0 dBmV

Posted by
Cable Expert

Member Since: ‎03-02-2007
Posts: 16,273
Message 6 of 14 (14,142 Views)

Re: Modem not working with cable splitter

Is that with the splitter or without?

 

Your signals are marginal as you posted.

 

Please share more on your wiring in the home like how many TV outlets, other splitters, and is this a single family home?  We need to figure out a way to increase the signal to that outlet, so you can add that splitter back in. 

Posted by
Connection Expert

Member Since: ‎06-30-2003
Posts: 7,155
Message 7 of 14 (14,141 Views)

Re: Modem not working with cable splitter


heatfan02 wrote:

This is with the splitter

 

Downstream Receive Power Level : -10.5 dBmV

Downstream SNR : 36.9 dB

Upstream transmit Power Level : 54.0 dBmV


that is bad

how is it without

Posted by
Edited on
‎04-25-2011 11:12 PM

Visitor
Member Since: ‎04-25-2011
Posts: 9
Message 8 of 14 (14,131 Views)

Re: Modem not working with cable splitter

[ Edited ]

That  was with the splitter. Here are the signals without the splitter.

 

Downstream Receive Power Level : -6.2 dBmV

 

Downstream SNR : 37.8 dB

 

Upstream transmit Power Level : 51.4 dBmV

 

It is a single family home with 4 bedrooms and 1 living room all with tv's in them. I'm pretty sure each room has 1 cable outlet.

   



Posted by
Visitor
Member Since: ‎04-25-2011
Posts: 9
Message 9 of 14 (14,094 Views)

Re: Modem not working with cable splitter

anyone know what the problem is?

Posted by
Connection Expert

Member Since: ‎12-24-2003
Posts: 49,739
Message 10 of 14 (14,089 Views)

Re: Modem not working with cable splitter

Yeah. There is too much attenuation in your line in the first place so you don't have enough wiggle room to allow for the additional loss that the splitter causes. It may be best to book a tech visit to investigate why and to correct the problem.

Posted by
Cable Expert

Member Since: ‎03-02-2007
Posts: 16,273
Message 11 of 14 (14,085 Views)

Re: Modem not working with cable splitter

it looks like you probably have too much splitting going on for your 4 TV outlets plus the cable modem, causing your signals to be too low to the modem when you add  that extra splitter.

 

Let us know how many ports are on the splitter for the TV outlets.

 

Please check the splitter you have feeding the TV outlets.  If you have any TV outlets that are not being used, you should unhook them at the splitter and change the splitter to something with less ports so you have less loss.

 

What should be done is from the coax coming in from the ground block outside, it should go to a  2-way splitter first, one leg feeding the jack to the cable modem.  The other leg should go to the input on the splitter for the TV outlets. 

 

We can get creative to get the splitters arranged to supply enough signal for each outlet, just post what you have going on now, and if any TV outlets can be disconnected so the splitter loss can be reduced.

Posted by
Problem Solver

Member Since: ‎06-27-2006
Posts: 849
Message 12 of 14 (14,071 Views)

Re: Modem not working with cable splitter

You also might want to try a tap instead of a splitter.

Posted by
Visitor
Member Since: ‎04-25-2011
Posts: 9
Message 13 of 14 (14,023 Views)

Re: Modem not working with cable splitter

The modem was working for about 2 days with the splitter, and it's not working again. Here is the event log to see if anyone can get something out of it. Please if anyone knows any solutions, let me know.

 

Thu Apr 28 19:41:52 2011 Thu Apr 28 19:41:52 2011 Warning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC...
Thu Apr 28 19:41:37 2011 Thu Apr 28 19:41:37 2011 Critical (3)No Ranging Response received - T3 time-out
Thu Apr 28 19:41:24 2011 Thu Apr 28 19:41:24 2011 Critical (3)Received Response to Broadcast Maintenance Request, But no Un...
Thu Apr 28 19:39:48 2011 Thu Apr 28 19:39:48 2011 Warning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC...
Thu Apr 28 19:39:30 2011 Thu Apr 28 19:39:30 2011 Critical (3)No Ranging Response received - T3 time-out
Thu Apr 28 19:39:15 2011 Thu Apr 28 19:39:15 2011 Critical (3)Received Response to Broadcast Maintenance Request, But no Un...
Thu Apr 28 19:37:38 2011 Thu Apr 28 19:37:38 2011 Warning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC...
Thu Apr 28 19:37:17 2011 Thu Apr 28 19:37:17 2011 Critical (3)No Ranging Response received - T3 time-out
Thu Apr 28 19:37:04 2011 Thu Apr 28 19:37:04 2011 Critical (3)Received Response to Broadcast Maintenance Request, But no Un...
Thu Apr 28 19:35:28 2011 Thu Apr 28 19:35:28 2011 Warning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC...
Thu Apr 28 19:35:08 2011 Thu Apr 28 19:35:08 2011 Critical (3)No Ranging Response received - T3 time-out
Thu Apr 28 19:34:52 2011 Thu Apr 28 19:34:52 2011 Critical (3)Received Response to Broadcast Maintenance Request, But no Un...
Thu Apr 28 19:33:16 2011 Thu Apr 28 19:33:16 2011 Warning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC...
Thu Apr 28 19:32:58 2011 Thu Apr 28 19:32:58 2011 Critical (3)No Ranging Response received - T3 time-out
Thu Apr 28 19:32:46 2011 Thu Apr 28 19:32:46 2011 Critical (3)Received Response to Broadcast Maintenance Request, But no Un...
Thu Apr 28 19:31:11 2011 Thu Apr 28 19:31:11 2011 Warning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC...
Thu Apr 28 19:31:02 2011 Thu Apr 28 19:31:02 2011 Critical (3)No Ranging Response received - T3 time-out
Thu Apr 28 19:30:51 2011 Thu Apr 28 19:30:51 2011 Critical (3)Received Response to Broadcast Maintenance Request, But no Un...
Thu Apr 28 19:29:14 2011 Thu Apr 28 19:29:14 2011 Warning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC...
Thu Apr 28 19:29:00 2011 Thu Apr 28 19:29:00 2011 Critical (3)No Ranging Response received - T3 time-out
Thu Apr 28 19:28:51 2011 Thu Apr 28 19:28:51 2011 Critical (3)Received Response to Broadcast Maintenance Request, But no Un...
Thu Apr 28 19:27:14 2011 Thu Apr 28 19:27:14 2011 Warning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC...
Thu Apr 28 19:26:57 2011 Thu Apr 28 19:26:57 2011 Critical (3)No Ranging Response received - T3 time-out
Thu Apr 28 19:26:45 2011 Thu Apr 28 19:26:45 2011 Critical (3)Received Response to Broadcast Maintenance Request, But no Un...
Thu Apr 28 19:25:08 2011 Thu Apr 28 19:25:08 2011 Warning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC...
Thu Apr 28 19:25:01 2011 Thu Apr 28 19:25:01 2011 Critical (3)No Ranging Response received - T3 time-out
Thu Apr 28 19:24:47 2011 Thu Apr 28 19:24:47 2011 Critical (3)Received Response to Broadcast Maintenance Request, But no Un...
Thu Apr 28 19:23:12 2011 Thu Apr 28 19:23:12 2011 Warning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC...
Thu Apr 28 19:23:00 2011 Thu Apr 28 19:23:00 2011 Critical (3)No Ranging Response received - T3 time-out
Thu Apr 28 19:22:52 2011 Thu Apr 28 19:22:52 2011 Critical (3)Received Response to Broadcast Maintenance Request, But no Un...
Time Not EstablishedTime Not EstablishedWarning (5)DHCP WARNING - Non-critical field invalid in response ;CM-MAC...
Time Not EstablishedTime Not EstablishedCritical (3)DHCP FAILED - Discover sent, no offer received;CM-MAC=f0:7b:c...
Posted by
Edited on
‎04-28-2011 10:49 PM

Connection Expert

Member Since: ‎12-24-2003
Posts: 49,739
Message 14 of 14 (14,007 Views)

Re: Modem not working with cable splitter

[ Edited ]

FWIW, those log entries only show one single event that is of a 20 minute duration so nothing of a really conclusive nature can be deemed from them, sorry. Those T-3 errors however do possibly show a RF related issue which has already been pointed out here.

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