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4. Splitters

If you can flag down a cable guy and convince him to give you some free splitters, then good for you. If you can't, then be prepared to spend some money.

Those cheap looking splitters they sell at Radio Shack are NO GOOD. Do NOT use combiner/splitters. Combiners trash digital signal and make it almost impossible for cable modems and digital boxes to talk back to your provider.

You want at least a 1GHz splitter. 900MHz usually work as well (unless your cable company actually goes above a gig, which I seriously doubt).
The 1GHz means that the splitter is designed to pass signals all the way up to 1GHz. You can use a splitter that says signals up to 2.5GHz instead of 1ghz however you wont need that expanded bandwidth for cable signals.

You may also have the option of buying power passing or not. You most likely do not need a power passing splitter. These are generally for special purpose applications (such as powering a signal amplifier that's in your attic from the outlet in your bedroom without running a power cord to it).

Also, do not get a bigger splitter than you NEED. The more ports a splitter has, the less signal it passes along to each port. Plus, they are more expensive.

Splitters are NOT made to connect wires together. I've been to many houses where people used an old crappy splitter they had laying around to hook up 2 or more short wires to each other because they didn't want to go out and buy a longer wire. SPLITTERS LOSE SIGNAL.

Good brands that I personally have dealt with are Monster (expensive), Regal, and Cablevision. I'm not incredibly fond of Magnavox splitters (usually found at K-Mart).

Feedback received on this FAQ entry:
  • If splitters reduce the input signal in proportion to the number of outputs, can the cable company boost the signal before it gets to your splitter? Also, does the cable company use splitters to serve multiple customers, say, within an apartment complex?

    2014-12-18 00:03:42

  • FOr the best results i would avoid using any of those splitters that say 5-900mhz because they are usually(always, in my observations) those splitters than internally consist of thin wire and ferrite cores that were great in early catv and matv systems, In modern cable you want splitters that are rated for 5-1000mhz because they, in my observation always contain a pcb with the electronics to keep good impedance matching across the band and provide high port isolation. Also look for soldered back splitter because it provides a more complete shield around the splitter electronics and in my experience most of the glued back splitters are the old thin wire and ferrite core type splitters and not the modern pcb type. When your looking for splitters find the data sheet and look for one that has either a conical, 4 sided, or some other form of high contact area seizure. Be careful using satelite splitters many of them only go down to 40mhz which cuts out the return path for cable.

    2014-06-16 12:54:16

  • What they really meant was that, with a 2 way splitter, you lose a bit more than half of the original signal strength from the input to the outputs, which would correspond to -3dB.

    2013-09-11 19:05:48

  • As a general rule splitters only attenuate 1/2 DB of signal. 2010-09-03 11:03:28 WRONG! A 2WAY loses a minimum of 3.5dB, a 4WAY loses 7dB and an 8WAY loses 10.5dB

    2012-10-22 13:24:49

  • When Iím out in the field I come across a wide variety of setups customers have created for themselves in the past, from running ancient wires to hooking up ancient $4 splitters that max out at like 200Mhz and I think were designed for aerial antennas in the 1970ís. Obviously the signal quality and overall performance was less then acceptable. After I fixed everything up, Iíve actually seen a huge improvement in response time with on demand, optimal signal strength with high definition channels, and a co worker of mine called it ďplant pristineĒ whatever that means lol. I definitely recommend checking out the Antronix CMC 3000 CamPort series. http://www.antronix.net/Products/camport.php It's a really really good price, you can order it through Amazon, and its pure perfection.

    2011-11-20 05:46:04 (Mike Wolf See Profile)

  • I got bored tonight and decided to search around the internet for the best splitters for digital cable and the range of prices that they come in. I was quite surprised at the simplicity and clarification that the Extreme brand comes with http://www.extreme-broadband.com/cable-splitters.php plus itís easy for both civilians and cable employees to order after making a free account. I've thought about getting the Monster Cable splitters but I just can't justify the $30 dollars for a 4 way splitter that I can get from Extreme for $12. I've been trained that when it comes to splitters with powerpass, that unless satellites are being used, that it will pass through dangerous surges that will fry the customer-premises equipment and cause fires, and generally the use of non powerpass splitters could act as fuse instead of passing it along.

    2011-10-29 05:40:59 (Mike Wolf See Profile)

  • A few weeks ago, I installed a monster 2 way splitter for my tv and modem. At first everything worked beautifully, but now I find myself constantly resetting the modem (power and receive lights are on, while send light is blinking). Any idea what is going on? If I connect my modem to the cable directly, things are ok as well. Is the Splitter defective? Thanks!

    2011-08-25 00:11:36

  • I deal with Regal and Antronix brands. Both are really good for div2, 3, 4, 8, but regal taps are a tiny bit better than antronix.

    2011-07-09 20:22:44

  • Will a 2-way video/cable tv splitter work between tv and cable modem?

    2011-02-05 13:37:18

  • As a general rule splitters only attenuate 1/2 DB of signal.

    2010-09-03 11:03:28

  • you are so right, i installed splitters from walmart, initially they worked, then the system degraded, then crashed, resulting in no internet for 3 days till cable guy told me it was the splitters! now internet is faster, TV is clearer. I have learned from this experience.

    2010-02-03 23:36:50

  • Heres is a link to a Cable Splitter Solution Center, it goes over everything from Seizure Mechanisms to Back Plate Design. I noticed none of these were mentioned in this FAQ http://www.yourbroadbandstore.com/solutions/when-to-use-a-cable-splitter.php?r=FRM02

    2009-05-21 10:23:30 (urbroadband See Profile)

  • That's really good information. Haven't played with the wiring lately, but if I do, I know where to start if there are junk splitters.

    2009-02-27 21:16:45 (jmc56 See Profile)

  • On service calls, I order and use the Extreme 5-1000 MHz splitters with my customers, work good with video, digital phone and HSD. I stay away from the Digi-max.

    2009-01-13 20:30:20

  • poor splitters will also give your local channels a ghosting effect. this is when a tv is tuning in two carriers for the same channel (Cable, and over the air transmission)

    2007-09-22 02:53:16

  • What happens if I use a splitter that says signals up to 2.5GHz instead of 1ghz

    2007-09-20 16:41:12 (molina0331 See Profile)

by Raydr See Profile edited by Axilla See Profile
last modified: 2007-09-20 18:13:49

Basically, you want to even out the signal distribution as much as possible between all of the TVs.

If you have a loop system, there isn't much you can do, but if you have a junction, spend a few minutes looking at the numbers on the splitter and see what you can come up with.

Remember that cable loses signal over distance.

by Raydr See Profile

You should have a 3 way splitter here. Put the modem on the 3.5db leg of the splitter, and the TVs on the 7db legs.

Feedback received on this FAQ entry:
  • yea they do three !!! but the customer can have the contracter put a tap on the line with a 18" jumper to a threeway or fourway !! that way the hsd is always on a direct line from the drop !!!

    2011-05-31 11:27:19

  • most cable companies allow for three drops in the price. so if you are not exceeding that you are legal.

    2011-01-31 15:21:04

  • HAHA - "is this legal"... you're funny.

    2011-01-02 13:23:58

  • is this legal

    2009-06-02 10:16:34

by Raydr See Profile

Usually you'll have a two way splitter at the top, with one 3.5 leg going to your cable modem. The other 3.5 leg will go to either a 3 or 4 way splitter, depending on your needs.

by Raydr See Profile

In this case I'd usually use a three way at the top.
The 3.5 leg on the first three way will go to a four way. The first 7 leg would go to the cable modem, and the second 7 leg would go to any TV.

The 3.5 and 7 leg can be swapped if the cable modem doesn't like it, but your TVs might be getting a little fuzzy at this point.

After 6 TVs, an amplifier is usually a good idea.

by Raydr See Profile

This one is easy:

A two way at the top, one leg going to the cable modem, and the other going to an 8 way. Cable modems do NOT like 8 way splitters, so try and keep it away.

You will most likely need an amplifier in order to have decent TV service (or you can just have some of your unused outlets turned off).

Feedback received on this FAQ entry:
  • Install the amplifier before the cable splitter, If you are using interactive services, such as on-demand, look for a bi-directional amplifier. If you have cable internet service place the modem on a 2-way splitter before the 8-way

    2009-05-14 11:47:18 (urbroadband See Profile)

  • Where would you place the amplifier? Before the in on the 8 way or for each TV.

    2007-12-26 15:42:35 (thxmike See Profile)

by Raydr See Profile
last modified: 2002-02-27 21:26:28

Mostly because they are not common. Although there are some situations where these rare splitters will fit in great, you'd probably have to order them online or from a special supply store.

You can do a pretty good job by just using 2, 3, 4, and 8 way splitters.

by Raydr See Profile

Each splitter is different, but here is what most of them mean:

The numbers on each OUT leg of the splitter show how much signal is lost after passing through that leg.

For example, a 2 way splitter has 3.5 on each leg. That means that 3.5db was lost as the signal passed through that leg.

Note: The signal loss written on splitters is how much is lost at around 50 to 100Mhz. The higher a frequency is, the more is lost over distance. This applies to splitters too. In reality, a cable modem is probably losing more like 4 to 5db when passing through this same splitter.

The following info provided by RadioDoc:
On the back of a splitter, you may see a number like 130db EMI etched into it. That's the ingress/egress suppression (shielding) spec for the splitter, e.g. if a +10 dBmv signal is present inside at the input, the maximum leakage from the splitter itself would be 10-130=-120 dBmv, which is very low. Same the other way...

by Raydr See Profile
last modified: 2002-03-08 20:59:40

Passive Splitters are the ones you see every day. They have an "In", and 2 or more "Outs". You hook them up, they do their thing, and you never touch them again. They do not require any kind of power to run.

Active Splitters run on power. Most active splitters also boost the signal a tiny bit to compensate for the signal that would usually be lost after passing through a passive splitter.

Do not confuse an Active Splitter with an Amplifier.

Feedback received on this FAQ entry:
  • So, does the 3.5db loss make a difference to my modem? To my TV? Is there such a problem as too much signal when using active splitters?

    2008-10-14 14:31:34

by Raydr See Profile
last modified: 2002-03-01 08:19:09

You may have been getting too MUCH signal. We do this sometimes to lower the amount of signal you are getting.

Also, he may have just been trying to be nice by leaving something you can plug your TV into.

Note by twisted2736 See Profile: or he/she (Tech) was out of barrels.

Feedback received on this FAQ entry:
  • My installer put in an Antronic CMC2002U with a load of some sort on one side. Can I replace it with a -3db barrel?

    2015-01-03 15:18:54

  • why not just use a 3 Db pencil pad?

    2009-10-31 02:56:04

by Raydr See Profile
last modified: 2005-05-17 09:50:58

This really can depend on your system and the type of splitter that you are using.

Here in Gainesville, we use terminators for three reasons:

1.) To prevent ingress from entering the system through an open port at the tap.
2.) To prevent signal reflections (which really isn't too big of a problem).
3.) To prevent cable theft.

Honestly, I doubt it would make much difference to have a terminator on a splitter in the home. If you want to do it anyway, you may be able to pick up a pack or something from Radio Shack.

You cannot use the ones that cable companies use, because they require a special tool to install/remove them (prevent cable theft).

Please see the definition for terminators for pictures of them.

Feedback received on this FAQ entry:
  • There is also a problem with egress or CLI which every cable system is told by the FCC to monitor closely because almost every time there is a leak there is a bandwidth conflict with. For example, if you have the right stuff leaking at a high enough strength it can take out over the air communications (like FIRE and POLICE)

    2007-09-22 02:59:18

by Raydr See Profile
last modified: 2002-03-07 20:04:43

Please go here:

Feedback received on this FAQ entry:
  • What happens if you connect the signal to one of the OUT ports on a two-way splitter? I want to have a 2-way splitter with the single (IN) port coming out the front of a wall plate. The cable carrying the signal would connect to the top OUT port, and a cable leading to another wall plate would be connected to the botttom OUT port. Will this affect picture quality?

    2008-11-12 21:25:02

by Raydr See Profile

I'm Going To Be Wiring My Home W/ (Wall Plates) RG6 In 8 Rooms
2 Per Room(In Case We Move TV To The Other Side Of Room), So 16 Splits + A Cable Modem

What's The Best Way To Do This?
Will I Need Terminators On The 8 Unused Splits,
Should I Terminate At The Splitter Or The Jacks?

This is a special situation and I highly recommend you get a 2 port AMP from your cable company.

My suggestion: Input going into 2 way splitter, one which goes to the cable modem, and the other going into the 2 port amp, and each port of the amp going into an 8 way splitter. This is of course if you want to have all 17 outlets active at once.

If you're just going to have 9 active, just use a one port amp going to a single 8 way. In this case you might not even need to use an AMP, depending on how strong of a signal the cable co pushes into your house.

Hope this helps!

by xer008 See Profile edited by Raydr See Profile
last modified: 2002-08-08 21:30:37

The options are really limited here, so just plug one into the 3.5 leg, and the other into a 7 leg.

Feedback received on this FAQ entry:
  • You might wish to review the previous entry.

    2011-04-26 12:05:08

  • Masturbation is the answer!

    2011-03-11 10:22:30

  • I would suggest getting a balanced 3-way splitter this will provide an equal loss of 5.5 dB on each leg.

    2008-11-10 17:24:08 (TTcntrctr101 See Profile)

  • Just a side note as a technical trainer for a large cable company in North Carolina... When available, you could also implement a balanced 3 way splitter which has 5.5db of loss per leg, connecting the two modems giving even distribution to all ports including the additional port for television services.

    2008-02-18 15:05:48

  • your best bet in this case would be to get your hands on a balanced three way splitter. the loss across all three legs is the same usually 5.5 dB

    2007-09-22 03:02:00

by Raydr See Profile
last modified: 2005-05-17 10:39:28