Splitter on my cable modem?

[blueonblack]

I finally just today entered the world of true unlimited broadband with my first cable modem. (I am so proud!)

I was at work during the installation and the installer put a splitter in the cable line, telling my wife it was *too fast*. ?! Sure enough, the cable comes out of the wall about 10 inches and into a 5-port splitter with only one line coming off it it, to the modem.

Why in the world would they do that? If I take out the splitter and put a simple union there will my service be any faster?

[x88x]

If I take out the splitter and put a simple union there will my service be any faster?
No. He didn't charge you for the splitter, did he? Either he was an incompetent fool or he was having a laugh at your expense.


I finally just today entered the world of true unlimited broadband with my first cable modem.
Not if you have Comcast.. :whistler:

Seriously though, congrats! It's a great feeling finally having a fast, reliable connection, I know. :D

[farlo]

all the splitter will really do is add noise to the line.

[Oneslowz28]

I was under the impression that splitters do in fact split bandwidth. That's why the big one that splits the main feed to your home is powered and acts to boost signal or something. Just something I was told a few years back.

[x88x]

If you've ever taken apart a power strip, a coax splitter is the exact same thing; just a bunch of plugs all hooked together. The reason why houses will sometimes need a booster (my parents' house has one) is because if there is too much wiring in the house, the signal coming in off the street won't always be strong enough to maintain a solid connection, and vice versa.

[Drum Thumper]

Oh boy, a thread I can add some of my expertise to -- your bandwidth is controlled by the config file that is sent from the CO (Central Office) to your modem. In a nutshell, when they provision your MAC (or C-MAC or HFMAC depending on brand of your modem) they have quite a few choices for up and down streams. The signal coming in might be too hot (for lack of a better term) before it gets to the modem, hence the need for the splitter. There's a number of different factors that your Tier 1 and Tier 2 tech support can look at when they pull modem stats -- dB (sometimes referred to as Signal/Noise) ratios, the .bin file, IP address, packets sent/received, etc etc etc. Some setups can even look past the modem and see what's hooked up behind it (well, see the MAC addy anyways).

Bottom line, if you take that splitter out, your connection may not even work. I'd leave well enough alone myself. The tech was probably trying to explain the situation at hand in laymans terms and got flustered by the beauty radiating from your wife.

Edit: here's some further reading if you're so inclined: http://en.wikipedia.org/wiki/DOCSIS

[x88x]

The signal coming in might be too hot (for lack of a better term) before it gets to the modem, hence the need for the splitter.

:? ?? How's that work? Every splitter I've taken apart has just been a straight physical connection, maybe providing the same resistance as a few more feet of cable. How would that alter the signal by an appreciable amount? :?

[Snowman]

Essentially what splitter does is reduce your gain, if your gain is too strong coming into the modem the automatic gain control circuit goes WTF and you have no internet.. same thing if it was too low. Depending on your provider depends on the frequency they use, most are now using sub band and control gain levels in pedestals but a lot also do it in a lot cheaper manner enter the splitter. Cable is notorious for not controlling their signal levels, if you have a friend with a spectrum analyzer have him hook it up and look at how all the peaks and valleys are uneven as hell.

A good splitter has minimal insertion loss and noise insertion, a cheap splitter essentially is the opposite. As long as your signal to noise ratio remains good you have no problems.

[x88x]

Huh, interesting. So basically the signal is just really dirty and if it's outside certain bounds the modem ignores it? If the amplitude is too low it needs a signal booster, too high and it needs some sort of resistance (in this case the splitter)? I would think you could get a 1-to-1 thing that would do the same thing but doesn't take up any more space than the cable, so you don't have a big splitter cluttering up the place.

Makes me glad I'm finally on fiber. :D (One of many reasons.)

[Snowman]

an attenuator (one to one thing) exists but on the whole costs about as much to a contractor as a cheapy two way splitter which can be used for a lot more things than just one.

[Diamon]

Man, the internet in the US seems so mumbo-jumbo. Having to fix the signal coming from the street. Bandwidth caps.. what's next? :P

[Snowman]

the internet kill switch bill is back on this time minus judicial review

[x88x]

Man, the internet in the US seems so mumbo-jumbo. Having to fix the signal coming from the street. Bandwidth caps.. what's next? :P

Plus, it's slower and more expensive than in most of Europe and East Asia. Yay USA. :P

[crenn]

You're whinging about slow and expensive internet? Try Australia's internet ;P

[Snowman]

You're whinging about slow and expensive internet? Try Australia's internet ;P

I thought you guys were still using carrier mail kangaroos and dial up.

[SgtM]

Drumthumper is right, with one exception. In the cable world, they're called head ends. The normal operating range for a cable modem is from about +7dB to -5dB. If the "tech" said he split it because it was too fast, he's a moron, and I would have told him so to his face. The signal strength coming out of the wall could have been too high, and that could be the reason. On a 2 way splitter, it's gonna drop the signal by 3.5dB, 3 way, 3.5 on one leg, 7 on the others, 4 way and up, it's -7dB all around. Typically though, they want the modem to be on the first split after the NID, on it's own line. Oh, and a house amp can't be used on a modem. They drop the return signal, so you'll get modem sync, but no surf.

Did I mention I used to be an installer? I have more than a couple lying around. :)
http://i47.photobucket.com/albums/f186/sgtm_usmc/de461c79.jpg

[Snowman]

Rick they have better house amps now that you can use on modem lines, just did an install a few months ago using one, don't do a lot of residential stuff though usually build satellite head ends to replace the cable in hotels because of the highway robbery rates haha. i had pictures of the 60 channel we just did.. but I can't find them so we got another one coming in soon I will have to take pictures... did I mention I have to do all this while in business dress attire...

[SgtM]

Definitely take pictures. This stuff is still interesting to me. In business dress? That sucks!

[crenn]

I thought you guys were still using carrier mail kangaroos and dial up.
Haha, NO! :P

The best tech we have is DOCSIS 3.0 but only in metropolitan areas (no where I am!) and you're very much capped. The ADSL2+ situation is a bit better, you're likely to have a cap (there is only 1 truly unlimited plan... but not available in my area) and the speed is certainly going to be a lot slower than cable, but you're going to be able to get it. And for people who think 3G is a good replacement for internet.... I want to shoot them... and I'm very much against guns :P

Bring on the NBN!

[Snowman]

I was using 3g just this morning while tethering my incredible.. whats wrong with 1 meg down and .7 up? not bad for being in an area where the only solution is dial up or wireless that comes in at about .5 meg down on a good day

[slaveofconvention]

I used to use 3g all the time when I was working security but I don't miss it. It's definitely better than dialup etc lol but I wouldn't want to rely on it as my only source of internet. I'm sitting considering an upgrade on my Cable service - I'm on 10mb at the moment but my provider now does 20, 50 and 100 *drool*

[Snowman]

I used to use 3g all the time when I was working security but I don't miss it. It's definitely better than dialup etc lol but I wouldn't want to rely on it as my only source of internet. I'm sitting considering an upgrade on my Cable service - I'm on 10mb at the moment but my provider now does 20, 50 and 100 *drool*

I will keep my 3g and my 100 acres of land and hopefully get some high speed at some point, until then I will take solace that if I want to go out on my porch in the morning stark naked with a cup of coffee I have that ability... not that I would want to but it is nice to know you have options :banana: