Sharing Cable Line????

vvinc2k · Post by **vvinc2k** » Thu Apr 26, 2001 5:37 am

Can a cable modem and a television share the same line on a 3 way splitter or does this cause problems?

I have a television and a cable modem split from the same line. The past week I have been getting time outs on everything I do, I have to refresh at least 4 times to get a website, about every 3-5 minutes my connection stops responding and then all of a sudden 30-90 seconds later it will kick back in. Is this because the splitter is on the line? I would hope its not because its been that way for over a month now and I have only had these problems this past week.

If you have any knowledge of this please icq me or post a reply here.

Thank you in advance...

bonebyten · Post by **bonebyten** » Thu Apr 26, 2001 3:52 pm

Get a dedicated line for your cable modem!

MaxMan · Post by **MaxMan** » Thu Apr 26, 2001 5:00 pm

It depends on what the signal is at the splitter and other factors.
Typically the modem is supposed to get a dedicated line at the ground before any other splitters that feed your house.
If the signal is good (>4dbmv)at that first splitter and there is no other integrity problems from that splitter to the modem, you should be fine. A 2-way splitter adds an attenuation of 3.5db on each leg. A 3-way has a 3.5db loss on one leg and a 7.5db loss on the other two.
Make sure that the modem is getting its signal from the first splitter.
I am an installer and I have had to re-do other butchers installs on service calls because they were split at second or third splitter down the line.

vvinc2k · Post by **vvinc2k** » Thu Apr 26, 2001 5:12 pm

Originally posted by MaxMan:
It depends on what the signal is at the splitter and other factors.
Typically the modem is supposed to get a dedicated line at the ground before any other splitters that feed your house.
If the signal is good (>4dbmv)at that first splitter and there is no other integrity problems from that splitter to the modem, you should be fine. A 2-way splitter adds an attenuation of 3.5db on each leg. A 3-way has a 3.5db loss on one leg and a 7.5db loss on the other two.
Make sure that the modem is getting its signal from the first splitter.
I am an installer and I have had to re-do other butchers installs on service calls because they were split at second or third splitter down the line.

The line dedicated for my cable modem comes straight in from the wall outside and into the splitter, then off the splitter I have a small 13 inch tv and the cable modem.

Here are the specs on the splitter:

2 Way Splitter
5-900Mhz

Here is a cheesey kind of example:

IN
(Cable from outside)

OUT OUT
(TV) (Cable Modem)

Terrible art there but hopefully in UBB it doesn't mess it up when I go to submit it, let me know if this is a problem

Thank you for your help...

[ 04-26-2001: Message edited by: vvinc2k ]

Pikap39 · Post by **Pikap39** » Thu Apr 26, 2001 11:21 pm

splitting the cable can cause problems. It is however more likely that the problem something other that that. As they said before it has to due with integrity and signal strength. Can you find out what your signal to noise is, and the signal level. These are important factors. As far as splitting the line its split a hundread time out on the main feed before it gets to you. There is no reason that you cant split it again as long as you follow the rest of the rules. I.E....make sure the signals good and the s/n is right.

Myzhi · Post by **Myzhi** » Fri Apr 27, 2001 12:17 am

It maybe that there is not enough signal strength to run both your TV and Cable modem at the same time. Test it out without your TV. If you internet connection works just fine then it's the signal strength issue.

MaxMan · Post by **MaxMan** » Fri Apr 27, 2001 5:19 pm

You should be ok with the way you described your setup. If you still have problems and you do not have the equipment to check your signal, you will need to call and get a service tech to come out.

vvinc2k · Post by **vvinc2k** » Fri Apr 27, 2001 5:23 pm

Originally posted by MaxMan:
You should be ok with the way you described your setup. If you still have problems and you do not have the equipment to check your signal, you will need to call and get a service tech to come out.

Service came out today, unhooked my setup saying that could be a probable cause, also they said I need to go to comcast @home and get a new ip address and that might fix my problem, they also suggested it might be noise in the line and they will send someone out this weekend to check the lines, they also tried telling me that my linksys 5 port hub was a router and not a hub and we argued with them for awhile that it was a hub and not a router.

Anyway I believe comcast has no clue what they are doing and I am about to tell them to shove it and go DSL here.

Hopefully they will figure out what they are doing and fix this because I am asking for free months till its working properly

Thanks for your help guys...

MaxMan · Post by **MaxMan** » Fri Apr 27, 2001 5:35 pm

It does sound like the tech that came out doesnt know what hes doing because he should have been able to check the lines.
It is a pretty straight foward process. If you have a good signal at the tap and it is not good at the modem, the problem is in your house. Maybe he found a problem at the tap, then a line tech will have to trace it from there.
I do not quite understand why you would need a new IP unless they are rebuilding your account and then they would have to change your DNS name also. Good luck.

Pikap39 · Post by **Pikap39** » Sat Apr 28, 2001 12:33 am

I hate to say this but sounds to me like you gat a DUD. Call again and get a real tech!!

eddiec · Post by **eddiec** » Sat Apr 28, 2001 1:10 am

Possible problem: you may have ingress from your TV. At the splitter there should be a mitigation filter on the video leg. It looks like a regular trap but is labled 5/13. If this is missing you're toast. I've seen a lot of people figure they were missing channels because of this so they remove it and the trouble starts. It does not affect TV reception. Really. When I set up an apartment I start at the service entrance and dedicate a line if I can. When that's impossible I put a splitter on at the wall plate and mitigate the video line. Another possible scenario is another splitter in the line between the tap and the cable modem that is allowing ingress. ALL video must be mitigated to prevent ingress.

vvinc2k · Post by **vvinc2k** » Sat Apr 28, 2001 1:46 am

Ok, there has not been a tv hooked up through the 2 way splitter all day and the problem still insists to happen.

I refuse to get another IP because I went through this before of someone else sharing the IP they gave me.

I am not very happy with Comcast and will be demanding a fre month every month till they get a clue to get off their areses and fix the problem.

I run a web design company from an office at home and each day that my connection is bad I lose money.

Going to call and complain to comcast on a daily basis till they fix it

rodrod5 · Post by **rodrod5** » Sat Apr 28, 2001 2:55 am

sounds like it is a potential stolen ip to me. just go to member services and sign up for a new one in ~30 minutes it will become active and then run with it for a day if it is ok then you know it was the ip, or have a friend ping the ip when you CANNOT ping out if he can ping it while you cannot ping out then unplug your modem if he can still ping the ip you have a stolen ip and the only way to solve it is to get a new one

also have you tried setting your self up static to see if this solves the problem? if it does it is probably a dhcp issue

when you ping to your gateway and the time outs occur are they sporadic or do they come in one continous string till you reboot? if the time outs are in ones and twos followed by more replies then it is probably line noise if it is continouse then i would lean more towards the ip

are you on a usb or a nic card and how many network adapters do you have in your machine?

does your modem lose sync when your pings stop? if so more of a modem or line noise issue .

let me know the results from the above ??s please thanks

[ 04-28-2001: Message edited by: rodrod5 ]

[ 04-28-2001: Message edited by: rodrod5 ]