Coax Splitters

Wyndru

Diamond Member
Apr 9, 2009
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I rewired the coax cable in my sister's house this weekend, because she had piggy backed radio shack gold splitters all over her house, and I'm still not happy with the results (although the TWC digital cable boxes are now working correctly). By results, I mean the signal power going to the boxes, when I go into the diagnostic menus, the numbers are in the yellow/red, so I know they are going to eventually have issues with on demand or HD broadcasts, even though they look fine while I was testing. I'm not in front of the box right now, but IIRC it's hovering around -15db.

Anyhow, right now the signal goes through 1 - 4way splitter, then 1 - 3 way splitter (one on each floor) before it gets to the box in question. I'm not sure if I set up the splitters correctly, but I kept the main line between the floors on the -3.5db leg. The second splitter only had -7.5db legs for all of them, so I think that might be causing too much of a drop in signal quality.

I have a 2 way splitter that has -3.5db on both legs, but I can't find anything larger (i.e. 3 - way splitter with -3.5db on all legs). Do these even exist? Are there good websites that sell high quality splitters? I've seen some splitters that don't even have db ratings on them, but instead have leg labeled "tap", I don't know what that means. Right now I'm using Regal 5-1000mhz.

I've asked Time Warner, but they want to send a tech out to install it, and I don't really want to go that route if I don't have to. I really just wanted to go to TWC and have them to give (or sell) me the splitters.

I'll admit, I don't know what I'm doing other than what I've read on the web, so I could be going about it in the wrong way, but I was able to get the SNR and power levels decent enough on the boxes so they actually work now...these are new boxes, and prior to the changes I made they were getting stuck displaying signal strength errors. I just wanted to see if there was a way to improve them more so they don't have any connection issues later. I'd prefer not to run direct lines from a single splitter if possible, and I've read that amps aren't recommended for digital since it introduces distortion.

Any suggestions?
 
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notposting

Diamond Member
Jul 22, 2005
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The Regal splitters are good (I still have my stash from my days working for Comcast).

So the first split is the 3 way, and the 4 way is coming off the -3.5 leg? That's about the the best you can do then. No other splitters involved? Taps aren't really used in home installations...here is a good explanation of them though: das linky.

Main problem with amps is the return signal necessary for cable modems/boxes.
 

Clixxer

Junior Member
Mar 8, 2013
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Amps can work its just how you do the wiring. Best thing to do with an amp is have your service line (line bringing service to the house), put a 2 way splitter on that. From the 2 way you will run one home run directly to the your modem (for internet, home phone, or both).

On the 2nd leg of the 2 way splitter run that to the amp. Now depending on if you have a 2 way or 4 way amp you feed your boxes directly off the amp or just put a 3 way splitter there.

For Time Warner the boxes will run just fine off an amp if you have it installed how I said.

Also as a former Time Warner Cable tech I hated regal splitters. In Dallas area if I saw one it got immediately replaced with a new one. I believe we used CommScope splitters but don't quote me on that.
 

smitbret

Diamond Member
Jul 27, 2006
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I am confused. You mentioned DTV so I assumed that meant DirecTV. Then you mentioned Time-Warner. It makes a difference because those Regal splitters won't work reliably with any satellite TV. Sat requires splitters rated at 2300Mhz or better.

I'd also look into all of the Coax. If you have any legs of RG59 it'll kill the signal for anything but a simple set of rabbit years. If you have it at any point near the origin it would be bad for anything further down the line. In fact, DirecTV installers are using RG-6 that has been swept to 3000Mhz.
 

Wyndru

Diamond Member
Apr 9, 2009
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By DTV I just meant digital tv (the boxes). It's Time Warner cable, I updated the post to avoid confusion, thanks for pointing that out.

I might look into an amp then. I wasn't sure if finding and installing a splitter with all of the legs at -3.5db instead of -7.5db would have helped. It would have only prevented a signal loss of -4db, which would put me into the acceptable range on these boxes according to the specs. I just haven't been able to find a 3 way with -3.5db on each leg, so I don't know if they exist. I have a 2 way like this, but anything larger I've found has only 1 leg with -3.5 and the rest -7.5.
 
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Clixxer

Junior Member
Mar 8, 2013
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By DTV I just meant digital tv (the boxes). It's Time Warner cable, I updated the post to avoid confusion, thanks for pointing that out.

I might look into an amp then. I wasn't sure if finding and installing a splitter with all of the legs at -3.5db instead of -7.5db would have helped. It would have only prevented a signal loss of -4db, which would put me into the acceptable range on these boxes according to the specs. I just haven't been able to find a 3 way with -3.5db on each leg, so I don't know if they exist. I have a 2 way like this, but anything larger I've found has only 1 leg with -3.5 and the rest -7.5.

As far as I know, a splitter with all legs -3.5 doesn't exist just just the -3.5, -7, -7.

Also like smitbret said make sure your coax is RG6. RG59 can work in some instances but it is very few and far between which makes its it virtually useless except in certain situations such as security cameras.
 

Wyndru

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Apr 9, 2009
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The next time I'm over there I'll check the cable type.

Was RG6 around in the 80's? D:

Crap, looks like I may need to run new wire after all.
 

NutBucket

Lifer
Aug 30, 2000
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Right, these are all passive splitters. By definition you take a signal and split it the power drops relative to the number of outputs: 2 outputs, 1/2 the power (-3dB). 4-way, 1/4 the power (-7.5dB).

Do you NEED to rewire the existing RG59? Depends. Yes, it is more lossy but unless you have a hundred feet of the stuff it probably won't matter.

And how many TVs are in this house? Your description says 4 floors, 3 outlets per floor?!?!
 

Wyndru

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Apr 9, 2009
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Right, these are all passive splitters. By definition you take a signal and split it the power drops relative to the number of outputs: 2 outputs, 1/2 the power (-3dB). 4-way, 1/4 the power (-7.5dB).
That makes sense and I thought that was how it worked, but I've also seen 5-way splitters where 1 leg has -3.5db, and 4 legs have -7db. I've also seen 2-ways that both have -7db, and others that both have -3.5db.

Do you NEED to rewire the existing RG59? Depends. Yes, it is more lossy but unless you have a hundred feet of the stuff it probably won't matter.

And how many TVs are in this house? Your description says 4 floors, 3 outlets per floor?!?!

6 TVs total.

Sorry, that was confusing also, I meant 1 splitter per floor, the 1st floor has a 4-way, 3 legs go to TVs (-7db), and the 4th (-3.5db) goes to the 2nd floor splitter. The 2nd floor splitter is a 3-way and each of those legs (-7db) goes to a TV.
 
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Clixxer

Junior Member
Mar 8, 2013
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6 TVs with digital boxes? Also is their any splitters outside? So your basic layout is:

Service line (from outside) ---> 4 way splitter ---> 3 way splitter ---> tv.


I would just use an amp. Typically anytime you have 4 or more pieces of equipment and you run into signal issues from outside not being enough.
 

Eug

Lifer
Mar 11, 2000
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I called Rogers cable to my house several times:

Original house wiring was RG59 (from the 90s), with RG6 wired from the pole to the house.

Adding a few RG6 lines in the house and replacing all the crap splitters with good ones helped things, but I still had some dropouts.
Then they added a signal amplifier and it helped things, but I still had some dropouts.
Finally they removed the RG6 from the pole and swapped in RG11, and everything is fine now.
I also replaced some of my other RG59 lines in the house with RG6.

Note that there are varying grades of RG6. I bought some cheap builders' grade stuff at the local hardware store and some expensive Belden stuff. All are way better than old RG59, but the Belden RG6 does give me an extra dB vs. the builders' grade RG6 over residential lengths IIRC. Not enough to make a huge difference, but not completely insignificant either. Unfortunately, the Belden stuff was several times the price.

EDIT:

The significant signal strength improvements were really at the highest frequencies.

Belden 1694A RG6 > Coleman Cable 92001 RG6 >>> old RG59

Over just a short distance of about 65-75 feet:

RG59 ~ 65 feet:
Channel 561, 111 MHz: -1 dB
Channel 055, 525 MHz: -7 dB
Channel 111, 669 MHz: -8 dB
Channel 534, 759 MHz: -10 dB <-- This is in the iffy zone according to my cable box.
Channel 560, 801 MHz: -12 dB <-- Ouch

New RG6 dual shield 92001 with 40% braid. The run is somewhere 75 feet&#8230; which is probably around 10 feet too long since I left a lot of extra cable on each end just in case I screwed up the terminations.

Channel 561, 111 MHz: 0 dB
Channel 055, 525 MHz: -4 to -5 dB fluctuating
Channel 111, 669 MHz: -6 dB
Channel 534, 759 MHz: -8 dB
Channel 560, 801 MHz: -9 dB solid

With new Belden 1694A:

Channel 561, 111 MHz: 0 dB
Channel 055, 525 MHz: -4 dB
Channel 111, 693 MHz: -6 to -7 dB fluctuating
Channel 534, 759 MHz: -8 dB
Channel 560, 801 MHz: -8 dB solid
 
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Wyndru

Diamond Member
Apr 9, 2009
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6 TVs with digital boxes? Also is their any splitters outside?
No splitters outside, 2 digital boxes upstairs, 1 downstairs. The rest are just coax straight to the TVs.

So your basic layout is:
Service line (from outside) ---> 4 way splitter ---> 3 way splitter ---> tv.
There is actually 1 more splitter where the service line comes into the house for the cable modem, so the furthest digital box is on a layout like this:
Service line (from outside) ---> 2 way splitter ---> 4 way splitter ---> 3 way splitter ---> cable box.

I would just use an amp. Typically anytime you have 4 or more pieces of equipment and you run into signal issues from outside not being enough.
I might try that if they have issues. I just spoke with her yesterday and they said that all 3 boxes have been fine, and they have been using on demand with no issues. Maybe the signal reading on the box wasn't that bad after all (or the warnings are conservative).
 

notposting

Diamond Member
Jul 22, 2005
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Well, one thing about that is you can fiddle with the setup a bit if needed.

I see a lot of "the cable modem must be on a 2-way splitter first" nonsense, in all reality you want it on the FIRST splitter...even if you have it on a -7 leg on a 4-way signal strength should* be fine (or if using a 3-way, put the NEXT splitter on the short leg).
 

Clixxer

Junior Member
Mar 8, 2013
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Wyndru if everything is working I would just leave it alone. Time Warner boxes and modems are conservative in their readings. Now would I let something into the red? Never but the yellow warning is fine. When I was a install tech for them I never even looked at signal I always looked at channels. I dunno if they have a different system where you are at vs Dallas but I just checked channels 3, 21, 89, 126 and if those came in clear I was good along with the HD channels. I Also looked at raw db reading from the outlet using my meter for those channels.

Anyways if she isn't having any problems I would leave it alone unless you just want to do something.
 

Wyndru

Diamond Member
Apr 9, 2009
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Wyndru if everything is working I would just leave it alone. Time Warner boxes and modems are conservative in their readings. Now would I let something into the red? Never but the yellow warning is fine. When I was a install tech for them I never even looked at signal I always looked at channels. I dunno if they have a different system where you are at vs Dallas but I just checked channels 3, 21, 89, 126 and if those came in clear I was good along with the HD channels. I Also looked at raw db reading from the outlet using my meter for those channels.

Anyways if she isn't having any problems I would leave it alone unless you just want to do something.

I think that's where I'm going to leave it for now. If I see any issues, I might try notposting's suggestion of running a 3-way for the 1st splitter where the service line comes in, just run the modem off the -3.5 leg, and have one leg going directly to the 1st floor and another going to the second floor. That way I cut out running through 1 splitter for the second floor (which is where I expect a problem, if one even arises).

Thanks for all of the suggestions!
 

Eug

Lifer
Mar 11, 2000
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Where I live, the first split is not user modifiable. It's in a locked box outside the house. Mind you, you can buy the tool to unlock it for $5 on eBay.
 

Wyndru

Diamond Member
Apr 9, 2009
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Yeah that's the way it is with my house (FIOS), Verizon has it locked in a box.

For my sister's TWC installation it's just hanging in her basement where the line comes in from the street.