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Raz1r
03-03-2008, 11:57 PM
I have a long line of CAT5 running from the family's wireless router, but it's starting to affect my performance. Sometimes I'll start to get packet loss and I'm pretty sure it's something up with the cable, as I've never had problems with transfers between the two PCs/Xbox on my side. Anyways, I was looking into getting my own network going with a few Linksys devices. I'll be able to control every aspect of my network and I'll have more room.

There are a few on Craigslist and I could get a Cable modem (BEFSR41) a 5-port hub and a WRT54G for about $50.

So my question is, can I use two modems in the same house? And will it affect performance if I split the cable into my TV and into the router?

SgtM
03-04-2008, 01:29 AM
So my question is, can I use two modems in the same house? And will it affect performance if I split the cable into my TV and into the router?

You can, but without checking signal levels it would be hard to tell if there would be any degredation in TV or internet quality if you split it. Before doing that (and paying for the internet twice), I would check the long cable that you have running to the computer now. How long is it? Is it exposed and being walked on? Are the ends crimped securely?

Bopher
03-04-2008, 02:44 AM
I pretty sure your cable provider would want to charge you for the second modem on your system because of the different MAC address.

As for the signal degradation, how many time can you count on the line that it has been split. Usually you can split a regular cable connection about 4 times if I remember right before you start to see a effect on the tv signal.

If you do end up having to pay for you're own internet cable straight to your room, I did this with Adelphia when they were around, have a super low "satellite" package. I used it for my internet and the get the local channels when I had DirecTv. They just had to come out and unblock channel 80 on my house to get the internet. it cost me somewhere around $35 plus tax a month, $5 for modem rental and $10 for the cable service and $20 for the internet @ 1Mbps.

Luke122
03-04-2008, 12:39 PM
I've never tried to run 2 cable modems in the same house, but 2 ADSL modems = fail.

Rather than spend money on this, I would first try a new ethernet cable. Get yourself a new strand, with new ends on it. Try Cat6 if you can. When running the cable, try to avoid electric motors (fans, etc), flourescent lights, and other electrical devices. You might find that there's something along the line causing the interference, or even just a bad plug, kink in the cable, etc.

Oh, one more thought.. try a different port on the router also. :)

Raz1r
03-04-2008, 03:08 PM
Thanks for the replies everybody. I'm gonna try to run a new line of CAT6 from the router and just pick up a WRT54G and the 5-port switch for expansion.

I'll call them today just to see how much they might charge me. Also, the cable has been split just twice.

I tried a different port on the router today, and I'm still getting intermittent packet loss during a games and such.

Luke122
03-04-2008, 06:31 PM
The cable has been split? As in damaged?

Bopher
03-04-2008, 09:32 PM
nah dude, just run through a splitter to run to different rooms.

Eclecticos
03-04-2008, 09:59 PM
I think the splitter is the problem. Run separate lines.

SgtM
03-04-2008, 11:25 PM
When I used to install cable, we had to do what was called a "home run" for modems. Basically, you bring the cable to the nid, terminate in the ground block. Then, run a cable into the house to a distribution point where your splitter(s) would reside. The modem HAD to be on the first split, so I would use a 2 way, one for the modem, and one for a 3 or 4 way for the TV's. Trouble starts after splitting and splitting and splitting. On a typical install, you'll have ~10db at the ground block. A good rule of thumb is +7db to -5db on modems, and 0db at the TV. That said, I have seen modems operate fine with as little as -20db. As far as signal loss, you can figure ~1db for every 100' of cable. Splitters are different. 2 ways will be 3.5db loss, 3 ways will have one port at 3.5db, and two at 7db. 4 way splitters and up have a minimum of 7db loss on all legs.

Two cable modems would work in the same house, but your MSO (cable provider) will undoubtedly want to charge you twice. There's no getting around calling them to make the 2nd modem work either.. they have to add the MAC address of the device to the system to allow it to talk.