Cable Modem\Cable splitter

[AtomicFire]

the two bad words that shouldn't go together!

Anyways, i'm planning on building a Mini-ITX MythTV Backend\Router box and theres a few issues that've come up.

The place where this box is sitting will have 1 coax cable connection. I need to plug 2 devies into it - a cable modem (The Linksys one, can't remember the model but its version 4) and a Hauppauge PVR-250 tuner card. I know cable modems are picky as hell in terms of the cable signal, so i'm a bit worried this will cause problems.

Our cable modem provider is BrightHouse (RoadRunner, Time Warner, whatever you want to call them) and we're getting a 10mbit\1mbit plan. I'm plannig on buying a 2-way cable amplifier designed to work with cable internet and has 2 outputs, then putting filters on the output to the TV card to filter out the Cable Modem signals and filters on the output to the Cable modem to filter out the TV signals.

The reason that i'm worried is because at my other place, I had an experience where if we used a splitter (some generic bottom-of-the-tooxbox version) to hook up a TV and a Cable Modem to the same line, then the spilitter would half the speeds the cable modem can get. Removing the splitter fixed the problem with the internet, though now we had to run a 50 foot coax cable to the TV and deal with a somewhat fuzzier picture on the TV.

Cliffs:
1. Getting cable internet + tv
2. Only have 1 plug
3. Splitter + 2-way amp + filters = good?

EDIT:
Just checked, the apartment has a junction box in a closet where the main cable line comes in, and is split by what looks like a good high-quality 5-1000MHz spilitter. However, there are markings on the outputs (5 total) where 4 are labeled "-7dB" and 1 is labeled "-3dB" - the ports have different output level? Which one is suppossed to have the stronger signal? I'm guessing the -3dB one...

 

[Xipher]

Odd, haven't had any problems with spliters myself, and I'm using cheap-o ones (no amplification, nothing).

 

[amenthes]

we used a splitter (some generic bottom-of-the-tooxbox version)

There's your problem. Don't use a crappy splitter. I use a decent quality two way splitter with no problems. It was something like 12 bucks @ radio shack if I remember. The key for splitters is that they pass the 5Mhz-1Ghz range or greater (though I've never seen one that didn't).
I've had troubles with amplified splitters in the past, but I've never had any issues with this splitter. I get the same exact speeds with or without the splitter (6Mbit). While the aplified splitter and filters may work fine, I say why get complex when you don't need to.

 

[movax]

I have a plain ol' 2-way splitter connected directly to the cable line coming in from outside (source line if you will). One of the outputs goes directly to my cable modem, no problem w/ download speeds or anything, and the other output goes to a cable amp, which then goes to a 5-way splitter for all the TVs.

 

[PanzerBoxb]

Before you start adding splitters I would recommend testing what power levels and signal/noise ratio you are getting straight off the coax.

 

[xxaaqq]

I did have trouble with a splitter at my house, until I called the cable company and they replaced the ancient wiring with new stuff. Then it worked fine.

 

[movax]

I did have trouble with a splitter at my house, until I called the cable company and they replaced the ancient wiring with new stuff. Then it worked fine.

One of my friends had to have his wiring replaced...it was from the 80s, and limiting his download speed. It was like...RG3-class, and rotted to hell.

 

[Frank4d]

When I got cable internet they came out and replaced the line between the box under the sidewalk up to my house because it was 30 years old. They put in a cheap $10 splitter and one line goes to the cable modem. The other output from the splitter goes to a low pass filter they installed. I connected an amplified splitter to the filter and run five TVs and three PC TV cards from it.