"Spliter/Signal Strength Problems with Modem"

Hey, I've been experiencing a rather odd problem.

I'll explain my situation:

Three years ago, we purchased cable internet. We had two other TV's in the house. The Cable Guy split the main connection using a Bi-Directional Splitter (Both outputs say 3.5 DB). One goes to the modem (using a heavy duty cable, not like the TV's cable) the other to another splitter, which goes to the TV Downstairs, and upstairs. Anyway, everything worked great. About two years ago, we split the upstairs connection into three, so there's an additional two TV's feeding off of the line (I was sure to purchase gold splitters from radio shack for minimal line loss).

About a month ago, I started experiencing problems with the modem and well, TV aswell. The quality of the television picture was garbage, and the internet would go down every time you used it, much to my annoyance. Even as we speak, it has JUST JUST come back up. and I've tried EVERYTHING, literally. The first thing I thought I'd do, was see if perhaps it was a splitter that was screwing things up. I checked, and the initial splitter (going from the main line) was a Regal splitter, that says "5-1000 MHz" and "110dB EMI Isolation". The two branches have 3.5 dB on them. It looks rather old, so I thought this could be the source of my problems. I went to Radio Shack and purchased a brand new "Bi Directional Splitter" that boasts "5-1100 MHZ" but mentions nothing about EMI Isolation. It too says 3.5 dB per branch. For awhile, this worked quite well, but within a couple hours, the problem returned.

I'm thinking, my problem is the signal strength. So I go out and purchase, from Radio Shack, a Bi Directional Signal amplifier. It claims to boost signal strength by 14 dB. It also stated that forward, it allows 1 - 1000 Mhz, while backwards, 10 - 50 Mhz. For awhile, this too worked. But every time, same problem. I've placed it in many different positions. In front of the first splitter, no go, after the first splitter, no go, right before the modem, no go. So I gave up on that $40 mistake. After much fiddling, I discovered how to restore the Internet. You do so by unplugging the TV's from the first splitter, and then rebooting the modem. Eventually, the modem comes back to it's "online" state. This was an interesting trick, so I thought perhaps it was a problem with the second splitter. $10 later, I found out, that splitter wasn't the problem. I then checked the little foot long line running from the first splitter, to the second splitter (remember, these lines are only for the television). Ah ha! It was loose! The head of the cable would seperate from the rest of the line. So I went out and purchased another small line for that. It worked, for the time being. But eventually, the same problem returned.

So here I am now. I have absolutely no idea why it's doing this and what to do. My television picture is crap, (mostly channel 2 - 13, coincidently, the same channels broadcast through the air). I've read about things like taps, or filters and what not, but I'm still just not sure what those are exactly, what to use, what to do.

Any help would be greatly appreciated.

-RD

I went the same route that you did, with the same results. I called the cable company and they said that you could not have a TV on the same line as roadrunner, even though they have a spliter where the line comes into the house (I had my TV and Modem on the same line for a couple of years with no problem). I ran another line from the other line to the TV that was hooked up on my modem line and now have no problem. I did put the amp on the other line and it helped all the TV's.
Hope this helps.

This response is over a year old, but i figure it might help someone with a problem.
To keep it simple, you only have a certain amout of singal coming into you house from the cable box. It all depends on the location you live and the condition of the main cable line in your area.
Okay, lets say you have an average of +5 Dbmv at the cable box. The time it reaches your house it is more than likely down to 0.0 which is what the cable company sets up because 0.0 is perfect with no signal lose and no noise interferance.
Now, you take that 0.0 and split it two way, now your down to about -4.0 on each split. This is still an okay number, but split that again and your at -8.0.. getting worse but still should work.
Basiclly, cable modems work fine with anything better than a -8.0 even thou most cable companys like to see it better than -5.0
Digital boxes can go as much as -10.0 but you will start to see delays in the digital pictures or it tiling in anything over -5.0
So unless you have a metter to messaure the signale strenght you are throwing dice the more you split it.
Amps work fine for tv boxs, but will not work with a cable modem. so if you amp your line, make sure you split the main line with one split going to the modem and the other split gong to the amp for tvs.
and always check your connections, loose fittings are the number 1 problem usally.