Are there any products available that will allow me to split my cable connection between my TV and modem? Right now I have Comcast basic cable with digital coming in about 10 days.

My cable modem (D-Link DCM-202 if it matters) and router are in an upstairs bedroom in my house, and I'd like to move them both downstairs so I can have a wired Ethernet connection for my Xbox 360 and PS3. I've tried a couple splitters from Radio Shack with no success. Do I need a specific part, or is what I'm hoping to do impossible? Thanks in advance for any input.

How (where)did you put the splitter in your system?

How (where)did you put the splitter in your system?

Wall outlet-->splitter; splitter-->TV, cable modem

Wall outlet-->splitter; splitter-->TV, cable modemThe cableco box and the modem are quite picky about signal levels. Ideally, you would have 2 direct runs from the pole. Otherwise, one split for the box and the other leg to the modem. The cableco tech should provide a splitter of the type they prefer, typically a 5-1000MHz, 2-way, with -3.5dB loss on each leg. Splitters with improper bandwidth will cause problems with OnDemand first and issues with your modem speeds. You can purchase a drop amp. I use a Motorola unit. Get the system working first before you start mucking with it.

YMMV

You mentioned that you tried a splitter from Radio shack, what was the frequency response? 5-1000Mhz (1Ghz).

If so were both the modem and TV reception bad or just one of them?
If you remove the splitter and run the connection directly to the TV is that okay?
Next run the connection directly to the modem is that okay?

You mentioned that you tried a splitter from Radio shack, what was the frequency response? 5-1000Mhz (1Ghz).

If so were both the modem and TV reception bad or just one of them?
If you remove the splitter and run the connection directly to the TV is that okay?
Next run the connection directly to the modem is that okay?

This (http://www.radioshack.com/product/index.jsp?productId=2103923&cp=2032057.2032187.2032188.2032195&pg=1&allCount=62&fbn=Price%2F%2410.00+-+%2449.99&searchSort=TRUE&fbc=1&retainProdsInSession=1&y=8&fr=StorePrice%2FRSK%2F00001000%2F00004999&x=11&s=A-StorePrice-RSK&parentPage=family) is what I bought. The picture to the TV was completely shot, and the modem didn't work at all, even when connected separately.

After reading some more, I think this (http://www.radioshack.com/product/index.jsp?productId=2103093&cp=&sr=1&origkw=cable+splitter&kw=cable+splitter&parentPage=search) is probably more what I need. I don't mind paying for it because I'll be able to sell my two wireless gaming adapters for more money than this would cost.

The cableco tech should provide a splitter of the type they prefer, typically a 5-1000MHz, 2-way, with -3.5dB loss on each leg.
Splitters with improper bandwidth will cause problems with OnDemand first and issues with your modem speeds. You can purchase a drop amp. I use a Motorola unit. Get the system working first before you start mucking with it.
YMMV
Agree 100%- Get the system working first before you start mucking with it.
If you do need a good bi-directional drop amp, please don't waste your money on the garbage RatShack sells- use a decent brand amp that will perform well for many years to come (I use the EDA-FT08100):
http://www.cabletvamps.com/drop%20amps.htm

I looked at that splitter and the amp and I didn't see any mention of the frequency response!
Before I would purchase an amplified device , I would try another passive splitter from somewhere else but make sure it has a range of 5-1000mhz.

OK, I'm confused.

Downstairs, I have my cable hooked up to my TV from the wall outlet with no problem. I don't have a box. Upstairs, the wall outlet is connected straight to my cable modem with no TV. It works perfectly also.

I want to move the modem downstairs and split the signal between my TV and modem. The passive splitter I tried garbled the picture to the TV, and the modem wouldn't resolve an IP address (flashing orange lights).

Those splitters replayrob linked to, do they work inside the house, or do I need to go outside and hook them up? If they go outside, that doesn't do me any good. I need something that will work inside. If those will do what I need, exactly which one on the cabletvamps.com page would I need?

Thanks to all who have posted so far.

OK, I'm confused.

Downstairs, I have my cable hooked up to my TV from the wall outlet with no problem. I don't have a box. Upstairs, the wall outlet is connected straight to my cable modem with no TV. It works perfectly also.

I want to move the modem downstairs and split the signal between my TV and modem. The passive splitter I tried garbled the picture to the TV, and the modem wouldn't resolve an IP address (flashing orange lights).

From this description it sounds like when you added the splitter your signal level is now to low to power anything.
Are there any other splits in your home that you are aware of?
I would hold off until the cable tech comes out to hook up your digital cable, after it is installed I would ask the tech to measure the signal level feeding your STB and tell the tech what you want to do, a simple 2 way splitter has about 3.5db of signal loss per leg.
If the level is to low to support a 2 way split find out if it can be increased by the cable-co.

If they can't do anything for you (they should be able to) you need more gain.

Keeping in mind that an appropiate splitter will cover 5-1000mhz.

From this description it sounds like when you added the splitter your signal level is now to low to power anything.
Are there any other splits in your home that you are aware of?
I would hold off until the cable tech comes out to hook up your digital cable, after it is installed I would ask the tech to measure the signal level feeding your STB and tell the tech what you want to do, a simple 2 way splitter has about 3.5db of signal loss per leg.
If the level is to low to support a 2 way split find out if it can be increased by the cable-co.

If they can't do anything for you (they should be able to) you need more gain.

Keeping in mind that an appropiate splitter will cover 5-1000mhz.

I'm not aware of any other splits in my house. I have only 2 TVs in the house, both hooked up directly to wall outlets, and the only other one is for the cable modem in the upstairs bedroom. I'll have to check the outside wiring.

I did swing by Rat Shack and bought that amp, just on the off-chance it might work. I really would like to get something set up tonight because I'm scheduled for a Gears of War party with some friends over Xbox Live tomorrow night and my digital cable isn't being installed until the 26th. I'll give it a shot, and if it doesn't work I'll probably just move my 360 upstairs and hook it up to my router and PC monitor until then.

I am using this unit for my remote location Motorola 484095-001-00 Signal Booster (http://www.amazon.com/Motorola-484095-001-00-Signal-Booster/dp/B000066E6Y)

YMMV

Hook up your cable modem so that it works.

Then, in your web browser, type in the IP address 192.168.100.1 - just the numbers, no www or http, etc. This should open a web page that shows some information about your modem.

Tell me what the numbers are for the following (or similar) three items -

Downstream Receive Power Level

Downstream SNR (signal to noise ratio)

Upstream Transmit Power Level

This will at least give a good idea about what's going on with the modem.

Actually, do it both ways. First, when it's working, then add the splitter (not amplifier) like you want to do and retrieve the numbers that way too.

I tried out that Rat Shack amp I linked to in an earlier post. Everything hooked up just fine, and both the TV and modem work perfectly as well. I went through a battery of speed tests at dslreports.com and speakeasy.net, each with good results. I played Gears of War co-op over Xbox Live with minimal lag. We'll have to see how it goes when the digial cable comes, but I'm happy so far.

Here are those numbers as reported by my modem. This is with the amp connected and the gain at slightly less than halfway. If these are out of whack or could potentially lead to problems down the line, please let me know.

Downstream:

Channel power: 9.5 dBmV
SNR: 33.403 dB

Upstream:

Channel power: 42.0 dBmV

Edit: With the gain on the amp turned all the way down, I get the following.

Downstream:

Channel power: 4.1 dBmV
SNR: 33.497 dB

Upstream:

Channel power: 42.0 dBmV

A quick Google search is showing that my channel power should be in the range of -8 to 8, with a downstream SNR above 30 and an upstream SNR below 55. Looks like I'm good here.

Your numbers look good with and without the amp and a 2 way split should not have hurt your cable modem.

and an upstream SNR below 55. Looks like I'm good here.

That is a strange spec, if anything that should be upstream channel power below 55dbmv.

Good luck with your new service and if any issues arise you know where to ask!

Looks OK either way as RCbridge said. However, it sounds like both tests were with the amp in the circuit so the test was not really of the arragement that didn't work.

It would have been interesting to see the signal info with the modem connected directly to the cable feed, and then again connected to the cable and splitter arrangement that did not work.

Your numbers look good with and without the amp and a 2 way split should not have hurt your cable modem.

It's entirely possible that the first splitter was defective in some way. Knowing my luck with electronics, I would say it's pretty darn likely LOL. :p

In any case, everything seems to be working just fine. My laptop is perfectly content accessing the Web wirelessly, and my consoles are operating normally. Again, big thanks to everyone for their input. :)

You can use a "Drop Amplifier".

It has 1 Inputs and various outputs that has gain in the 50-1000MHz range which will provide you more level to the modem and also to your digital setop box.
The Digital tier fo the Cable system requires a minimum threshold and this drop amp can help you maiting that minimum level.

A plain splitter has loss of 3dB ( 1/2 power).


You can get them at retail or ask you cable company to install for you.

Well, rather than buying amps, one should get the cable co to fix a crappy signal - assuming that's the problem (which I'm skeptical about, BTW).

The cable co signal should be strong enough for a two-way or three-way split without an amp. The modem signal with the amp turned all the way down sorta showed that - although even turned all the way down it may still provide some signal amplification.

Chances are, when they come to install the digital STB, they'll want to take the Rat Shack amp out of the line.

Chances are, when they come to install the digital STB, they'll want to take the Rat Shack amp out of the line.

I will probably remove the amp before the cable co shows up and tell them when they arrive that I'd like to have it split. Everything will already be downstairs, all they'd have to do is make sure they install it properly--they won't be allowed to leave until it is.

Yeah, just be aware that the "cable guy" may charge you for extra work he does to install other hookups. A service upgrade typically does not include extra wiring - it's merely remove the old STB, check the signals, install the new STB. If the main feed is out of spec typically that's fixed at no extra charge.

Around here, I think it's like $30 1-time charge for each addtional hookup. He will almost certainly want to install "home runs" of cable for the extra devices that go all the way back to the main feed point.

If you ask nice, he may leave you all the materials (coax, splitter(s), connectors, cable clamps/standoffs, etc) you need to do the job properly yourself at no extra charge.

Yeah, just be aware that the "cable guy" may charge you for extra work he does to install other hookups. A service upgrade typically does not include extra wiring - it's merely remove the old STB, check the signals, install the new STB. If the main feed is out of spec typically that's fixed at no extra charge.

Around here, I think it's like $30 1-time charge for each addtional hookup. He will almost certainly want to install "home runs" of cable for the extra devices that go all the way back to the main feed point.

If you ask nice, he may leave you all the materials (coax, splitter(s), connectors, cable clamps/standoffs, etc) you need to do the job properly yourself at no extra charge.

I guess we'll have to see what happens when he comes and what kind of guy he is. If he's nice and decides to do it out of the kindness of his heart, I'll probably slip him some cash. I have all the necessary coax cables. All he would really need to do is hook up the splitter. If he's going to charge me for that, I will take your advice and ask that he leave the materials so I can do it myself.