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What splitter do I need to split HD cable and internet?

post #1 of 29
4/17/12 at 7:48pm
Thread Starter 
Right now, this is how my Time Warner Cable line is split.

Code:
                               /---internet
                      /--------
                     /         \\---SD Digital Cable Box
Main Cable line------  
                     \\          
                      \\------HD Cable Box

My main cable line is split two ways. One half goes into my living room and into the HD box. Then the other half goes into the bedroom. In the bedroom is another splitter which splits the line into two again one for internet and another for a second cable box, but this one is just SD Digital, not HD.

Both splitters are 1 GHz splitters. The bedroom line is ok. The internet and cable box in the bedroom seem to work ok. However, the HD cable seems to have more problems. A good number of channels work fine. But occasionally, some channels would pixelate and skip. And some channels like NickHD, I would experience a brief picture freeze for a brief second or two and then the picture goes back to normal. The SD box doesn't seem to have nearly this many problems. I have to wonder if the coax cable going into my HD box is bad or the 1 GHz splitter may not be good enough for HD cable.

My friend gave me a 2 GHz splitter to try out. I replaced the main splitter in the living room. Oddly enough, the HD cable was working fine, but the internet wasn't getting a signal. Not sure if the splitter is bad or if the 2 GHz splitter is not good for internet. So I had to put back the 1 GHz splitter and the internet was working fine again.

Can someone tell me if that 1 GHz splitter is good enough to split my cable line? Or do I need to go up to 2 or 3 GHz for HD cable? If it's the latter, then why didn't my friend's splitter work for the internet?
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post #2 of 29
4/17/12 at 7:58pm
A 2 GHz splitter means it works up to the 2 GHz frequency. Seeing as your cable company's frequencies won't go past 1 GHz it's pointless. Also the signal to the internet is being split twice so that's not good. Why not post your signal specs from you cable modem for your internet and we can see if there is an issue.
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post #3 of 29
4/17/12 at 8:12pm
Thread Starter 
Well, the cable guy was the one that installed the two splitters. What should he have done? Put in one 3-way splitter??

And what do you mean by signal specs for my modem? Do you mean there is some sort of signal meter on my modem? If so, I will have to get back to you tomorrow. I'm not at home right now, so I can't check at the moment.
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post #4 of 29
4/17/12 at 8:22pm
Quote:
Originally Posted by MrHT View Post

Well, the cable guy was the one that installed the two splitters. What should he have done? Put in one 3-way splitter??

And what do you mean by signal specs for my modem? Do you mean there is some sort of signal meter on my modem? If so, I will have to get back to you tomorrow. I'm not at home right now, so I can't check at the moment.

Depending on your modem you type in 192.168.100.1 or something like that. You get to your modem configuration page. In there you should be able to see the signal levels. from those we can tell if there is a signal issue.

Splitting the signal twice means your losing 7 dB in signal strength. That could matter. I would have had the internet on one side and resplit the 2 TV signals.

Also I need to know what kind of coax you are using how long each length it is. Also if you have sharp bends in the coax that's not good. Could be some sort of interference.
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post #5 of 29
4/17/12 at 10:01pm
Quote:
Originally Posted by MrHT View Post

Right now, this is how my Time Warner Cable line is split.

Code:
                               /---internet
                      /--------
                     /         \\---SD Digital Cable Box
Main Cable line------  
                     \\          
                      \\------HD Cable Box

My main cable line is split two ways. One half goes into my living room and into the HD box. Then the other half goes into the bedroom. In the bedroom is another splitter which splits the line into two again one for internet and another for a second cable box, but this one is just SD Digital, not HD.

Both splitters are 1 GHz splitters. The bedroom line is ok. The internet and cable box in the bedroom seem to work ok. However, the HD cable seems to have more problems. A good number of channels work fine. But occasionally, some channels would pixelate and skip. And some channels like NickHD, I would experience a brief picture freeze for a brief second or two and then the picture goes back to normal. The SD box doesn't seem to have nearly this many problems. I have to wonder if the coax cable going into my HD box is bad or the 1 GHz splitter may not be good enough for HD cable.

My friend gave me a 2 GHz splitter to try out. I replaced the main splitter in the living room. Oddly enough, the HD cable was working fine, but the internet wasn't getting a signal. Not sure if the splitter is bad or if the 2 GHz splitter is not good for internet. So I had to put back the 1 GHz splitter and the internet was working fine again.

Can someone tell me if that 1 GHz splitter is good enough to split my cable line? Or do I need to go up to 2 or 3 GHz for HD cable? If it's the latter, then why didn't my friend's splitter work for the internet?

Question: What type of cable is used coming out of the first splitter, and how long is it? Otherwise, I'd try switching the two splitters and see if your problems move with the splitter. 1GHz splitters should be fine. Your system, as diagrammed, should work fine if the signal coming into your house is high enough.
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post #6 of 29
4/18/12 at 6:15am
Thread Starter 
Quote:
Originally Posted by BCF68 View Post

Splitting the signal twice means your losing 7 dB in signal strength. That could matter. I would have had the internet on one side and resplit the 2 TV signals.

I used to have that setup back in 2001 when I first got digital cable. But some channels weren't working. When the cable guy came, he removed that splitter and changed my setup into what it is now. It fixed the issue. Sometimes I wonder if these cable guys know what they're doing.

Quote:
Originally Posted by domino92024 View Post

Question: What type of cable is used coming out of the first splitter, and how long is it? Otherwise, I'd try switching the two splitters and see if your problems move with the splitter. 1GHz splitters should be fine. Your system, as diagrammed, should work fine if the signal coming into your house is high enough.

12 feet coax cable is what is coming out of the first splitter and into the HD cable box. I could get away with 8 feet, but can't seem to find anything of that length at the store.

I forgot to mention that I live in a 10 floor apartment. I'm on the 7th floor. I'm not sure if that makes a difference because maybe the problem could even lie somewhere in the wiring in the building. But that would mean that other people are affected and someone would've complained about it by now.
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post #7 of 29
4/18/12 at 6:45am
Quote:
Originally Posted by MrHT View Post

12 feet coax cable is what is coming out of the first splitter and into the HD cable box. I could get away with 8 feet, but can't seem to find anything of that length at the store.

That won't make a difference.

Quote:


I forgot to mention that I live in a 10 floor apartment. I'm on the 7th floor. I'm not sure if that makes a difference because maybe the problem could even lie somewhere in the wiring in the building. But that would mean that other people are affected and someone would've complained about it by now.

Yeah there could be an issue elsewhere. If you could post your modem signals that would help.

What I'm looking for is

Downstream; Power level and signal to noise ratio( SNR )

Upstream; Power level
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post #8 of 29
4/18/12 at 8:09am
Thread Starter 
I will be back home tonight to check my modem. Hopefully, I can figure out how to check the signal on it. I'm not very good with kind of thing, but I'll try. Heh!
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post #9 of 29
4/18/12 at 8:34am
Checking the signal levels via the modem is probably not an accurate benchmark as it is two splits away. The "problem" is at the first split (as indicated in the diagram).

So, I'd suggest temporarily removing the second splitter to get a more accurate reading that mirrors the signal(s) that the HD TV is receiving.

Going out on a limb... I'd suggest that there is a marginal HD receiver or a bad cable/connector feeding the HD set.
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post #10 of 29
4/18/12 at 9:29am
Quote:
Originally Posted by Ratman View Post

Checking the signal levels via the modem is probably not an accurate benchmark as it is two splits away. The "problem" is at the first split (as indicated in the diagram).

So, I'd suggest temporarily removing the second splitter to get a more accurate reading that mirrors the signal(s) that the HD TV is receiving.

He can check the signals at each split. Also he can hook up the modem to the incoming cable all by itself and check the signal. Also if he ends up keeping his arrangement the way he currently has it, it will matter what kind of signal he receives after 2 splits.

Also depending on the HD box you can check the signal strength coming into the box.
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post #11 of 29
4/18/12 at 11:18am
Yeah, okay... just sayin'

He has a problem at the first split.

If he can check the incoming on the HD box, that would be easiest and convenient. OTOH, maybe another service call would be better.

Nothing wrong with your suggestions and troubleshooting may seem simplistic to you and me. But... IMHO, if there's a problem with only one split, it's a bad coax cable/connector, STB or perhaps HDMI cable.
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post #12 of 29
4/18/12 at 11:49am
Quote:
Originally Posted by Ratman View Post

Yeah, okay... just sayin'

He has a problem at the first split.

If he can check the incoming on the HD box, that would be easiest and convenient. OTOH, maybe another service call would be better.

Nothing wrong with your suggestions and troubleshooting may seem simplistic to you and me. But... IMHO, if there's a problem with only one split, it's a bad coax cable/connector, STB or perhaps HDMI cable.

Sure could be bad cable or splitter. Doesn't hurt to narrow things down and possibly fixing a minor problem without a service call. Besides a lot of these service guys are contract workers that are frankly morons. I'm just saying that if he can get a good signal on his cable modem after 2 splits then it probably isn't a signal issue. The OP is making sound like it's recent service so his cables, connectors, and splitters should be new. SHOULD BE is the operative word.
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post #13 of 29
4/18/12 at 3:37pm
Thread Starter 
Ok, I'm at home now and checked the cable modem. I don't know how to check the signal on this thing. If you can tell me how, I'd greatly appreciate it.

I found a picture of my modem. Here it is....

http://www.atlantisgadgets.com/image...able_Modem.JPG
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post #14 of 29
4/18/12 at 4:16pm
Quote:
Originally Posted by MrHT View Post

Ok, I'm at home now and checked the cable modem. I don't know how to check the signal on this thing. If you can tell me how, I'd greatly appreciate it.

I found a picture of my modem. Here it is....

http://www.atlantisgadgets.com/image...able_Modem.JPG

just type 198.162.100.1 into your browser address bar
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post #15 of 29
4/18/12 at 5:39pm
Thread Starter 
Ok, got it. It was actually 192..., not 198.

Cable Signal Details

Forward Path:
Signal Acquired at 297.000 MHz
SNR: 39.3 dB
Received Signal Strength: -0.5 dBmV
Bit Error Rate: 0.000 %
Modulation: 256 QAM

Return Path:
Connection: Acquired
Frequency: 23.8 MHz
Power Level: 38.7 dBmV
Channel ID: 2
Modulation: 64 QAM

Let me know if this is good or bad. Thanks! Much appreciated!
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post #16 of 29
4/18/12 at 7:12pm
Quote:
Originally Posted by MrHT View Post

Ok, got it. It was actually 192..., not 198.

My bad, brain fart.

Quote:


Cable Signal Details

Forward Path:
Signal Acquired at 297.000 MHz
SNR: 39.3 dB
Received Signal Strength: -0.5 dBmV
Bit Error Rate: 0.000 %
Modulation: 256 QAM

Return Path:
Connection: Acquired
Frequency: 23.8 MHz
Power Level: 38.7 dBmV
Channel ID: 2
Modulation: 64 QAM

Let me know if this is good or bad. Thanks! Much appreciated!

Those look fine. Is that with your modem hooked up the way you posted in your diagram? If so there is definitely not a signal issue. Since you tried different splitters I don't think that's it. So it's either bad cabling or a bad HD box or perhaps some issue with the fact your in an apartment building. How do you have the HD STB hooked to the TV?
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post #17 of 29
4/18/12 at 7:32pm
Thread Starter 
Quote:
Originally Posted by BCF68 View Post

Those look fine. Is that with your modem hooked up the way you posted in your diagram? If so there is definitely not a signal issue. Since you tried different splitters I don't think that's it. So it's either bad cabling or a bad HD box or perhaps some issue with the fact your in an apartment building. How do you have the HD STB hooked to the TV?

Yes, that's my cable signal after it's split twice. If the internet is fine after being split twice, then I don't see why my HD cable is acting funky when it's only split once.

The HD box is hooked up via HDMI to the TV. But that can't be the issue because I use HDMI for my DVD & BD players and don't experience such issues. And the skip/pixellation & freezing frames only occur in about 10% of the channels. Some channels may have a brief skip once every hour and some may occur once every 20-30 minutes. NickHD is the worst as the frame will hang for a few seconds and then resume and it happens once every 5-7 minutes. But most HD channels which I watch often like TBS, E!, Discovery, AMC, etc. work perfectly fine. I guess a few channels just have weak signals but I'm not sure why.
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post #18 of 29
4/18/12 at 8:03pm
Quote:
Originally Posted by MrHT View Post

The HD box is hooked up via HDMI to the TV. But that can't be the issue because I use HDMI for my DVD & BD players and don't experience such issues. And the skip/pixellation & freezing frames only occur in about 10% of the channels. Some channels may have a brief skip once every hour and some may occur once every 20-30 minutes. NickHD is the worst as the frame will hang for a few seconds and then resume and it happens once every 5-7 minutes. But most HD channels which I watch often like TBS, E!, Discovery, AMC, etc. work perfectly fine. I guess a few channels just have weak signals but I'm not sure why.

Could be an issue with a specific channel. Especially if it's always the same channel having the issue. Have you tried eliminating all the splitters and just hook the HDTV directly to the main line and see if the issue still appears? Can you find out the model of the HD cable box.
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post #19 of 29
4/18/12 at 8:48pm
Quote:
Originally Posted by MrHT View Post

Yes, that's my cable signal after it's split twice. If the internet is fine after being split twice, then I don't see why my HD cable is acting funky when it's only split once.

The HD box is hooked up via HDMI to the TV. But that can't be the issue because I use HDMI for my DVD & BD players and don't experience such issues. And the skip/pixellation & freezing frames only occur in about 10% of the channels. Some channels may have a brief skip once every hour and some may occur once every 20-30 minutes. NickHD is the worst as the frame will hang for a few seconds and then resume and it happens once every 5-7 minutes. But most HD channels which I watch often like TBS, E!, Discovery, AMC, etc. work perfectly fine. I guess a few channels just have weak signals but I'm not sure why.

Your modem downstream channel is RF channel 36 and your SD digital cable channels are probably on RF channel assignments below RF channel 90.
Your HD channels are probably on RF channel assignments above RF channel 100 to RF 135.
The channels that have the most drop outs is closer to RF channel 135 and the channels with the minor drop outs are probably in the RF 110 to 120 range.

The likely problem is with the feed coming from the distribution point in the basement of your building to your apartment on the 7th floor. You will have to find out from the apartment owner/owners who is responsible for the cable feed inside the building. The feed to your apartment can be older R59 cable or even damaged by rodents.
Another possibility is the whole distribution system needs to upgraded to handle the higher frequency channels.
You can try calling the cable company and see if they can send a tech out to check the signal strength and SNR of the higher frequency channels. They then can determine who will be responsible for the repairs/upgrades.

If you have a Motorola HD box you can check the signal quality using the diagnostics built into the box.
With the tv and box on ,tune to one of the bad channels, press the cable button then the power button, then quickly followed by pressing the ok/selct button. This will show the diagnostics.
Arrow down to the inband tuner and you will see the frequency of the channel in MHz and also the SNR of the channel. If the SNR is in the twenties and lower this will mean that there is a issues with the higher frequency channels.
You can use this chart to locate the RF channel assignment by its frequency in MHz:
http://en.wikipedia.org/wiki/North_A...on_frequencies
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post #20 of 29
4/19/12 at 6:02am
Thread Starter 
Quote:
Originally Posted by BCF68 View Post

Can you find out the model of the HD cable box.

Samsung SMT-H3050
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post #21 of 29
4/19/12 at 6:31am
Thread Starter 
Quote:
Originally Posted by Jed1 View Post

The feed to your apartment can be older R59 cable or even damaged by rodents.

Maybe that is the issue. The cable coming from my splitter to the HD box is RG6 because I bought that myself since I needed a longer cable after I moved my TV to the other side of the living room. But the cable that's before the splitter, I don't know because it was the cable company that put those cables in. Maybe they're old RG59 cables like you said. But it was weird because there were a few times when I had a lot of problems with SD digital cable several years ago and when a cable guy came, he just replaced the splitter and all was good after that. You'd think he would've replaced the cables in my apartment if he saw they were old R59 cables.

I guess I would have to give Time Warner a call and have them send someone over. I usually prefer not to because it's usually a waste of time since I'm never usually happy with the results. But it looks like I don't have a choice.

Thanks for the help!
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post #22 of 29
4/19/12 at 8:04am
Just for kicks... do you have a set of component cables? Try them instead of HDMI from the STB to the TV.
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post #23 of 29
4/19/12 at 6:03pm
Quote:
Originally Posted by MrHT View Post

Maybe that is the issue. The cable coming from my splitter to the HD box is RG6 because I bought that myself since I needed a longer cable after I moved my TV to the other side of the living room. But the cable that's before the splitter, I don't know because it was the cable company that put those cables in. Maybe they're old RG59 cables like you said. But it was weird because there were a few times when I had a lot of problems with SD digital cable several years ago and when a cable guy came, he just replaced the splitter and all was good after that. You'd think he would've replaced the cables in my apartment if he saw they were old R59 cables.

I guess I would have to give Time Warner a call and have them send someone over. I usually prefer not to because it's usually a waste of time since I'm never usually happy with the results. But it looks like I don't have a choice.

Thanks for the help!

It doesn't hurt to try. You never know, if you get a good tech, maybe they will upgrade the coax in the building. It might even be a simple fix.
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post #24 of 29
4/20/12 at 6:07am
Thread Starter 
Yeah, true. The thing is... my experience with them has never been all that great. And my uncle hasn't either. I remember he subscribed to their HD service a year ago and had a lot worse problems than me. Some channels would freeze & lock up, some would have sound with no picture and some will just not work at all. He had a tech come over twice and they weren't able to help. They just simply rebooted his box and they guy told him that he needs to reboot his box daily. It's a weird story but that's what my uncle told me. He finally had enough and switched to Verizon Fios and has never looked back. He said Fios almost never has issues. Unfortunately, my building doesn't have Fios, so I don't have that option.

Like you said, maybe I'll be real lucky and get a good tech, but I'm not holding my breath, lol.
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post #25 of 29
4/22/12 at 9:38am
Don't rule out the possibility of a bad splitter. I've seen just 1 port go south more than a few times.
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post #26 of 29
4/22/12 at 5:01pm
Thread Starter 
Weird. Seems like most of the channels are working fine now with the exception of Nick HD which still has those occasional freeze frames. I just got their HD service a week and a half ago, so maybe it takes time for them to send all the proper signals to my box. But I've been watching all weekend and with the exception of Nick HD, I had no problems with all the several other HD channels I've watched. Maybe something is wrong with Nick HD. Very odd!
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post #27 of 29
4/22/12 at 9:30pm
Quote:
Originally Posted by MrHT View Post

Weird. Seems like most of the channels are working fine now with the exception of Nick HD which still has those occasional freeze frames. I just got their HD service a week and a half ago, so maybe it takes time for them to send all the proper signals to my box. But I've been watching all weekend and with the exception of Nick HD, I had no problems with all the several other HD channels I've watched. Maybe something is wrong with Nick HD. Very odd!

I have Charter and for awhile we had problems with USA-HD. The sound would break-up or even would go out for hours sometimes. The SD version would be fine. All the other channels were fine. We had 2 TVs with 2 HD boxes both had the same issue with USA-HD. So it wasn't a STB issue or a TV issue or a HDMI issue. Then one day it went away and hasn't been an issue since. What was the cause, I don't know?

maybe you could ask some of your neighbors that have HD service if they are having the same issue.
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post #28 of 29
4/23/12 at 7:51am
Thread Starter 
But it's weird. Two weeks ago when I just got Time Warner's HD box, most of the channels would skip or pixellate occasionally. Now, all of them have self corrected themselves and only NickHD is having issues. I also noticed that TW gave me all the premium channels free for the first week. Maybe it was accidental because once they shut them off, that's when I started noticing that the HD channels were working fine. Sounds like a setup problem on TW's end. Who knows? Maybe NickHD will eventually self correct with time.
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post #29 of 29
4/26/12 at 5:29pm
Thread Starter 
Quote:
Originally Posted by BCF68 View Post

Have you tried eliminating all the splitters and just hook the HDTV directly to the main line and see if the issue still appears?

I just did that test yesterday. When I removed the main splitter, NickHD still had the problem. So, this narrows down the issue to one of three things:

1) The wiring in the building is bad. Like Jed1 said, maybe the cables in the building are not working well with NickHD since it's possible that this particular channel is using a very high frequency.
2) The cable from the splitter to the HD box is bad.
3) Something is wrong with the channel.

Just for the heck of it, I've ordered a 10 feet RG-6 coax cable from monoprice today. When that arrives, I will replace the 12 feet coax cable that runs from the splitter to the HD box. If the problem persists, then we can rule out #2. I figured I'd give this one last shot before I call the cable company because once we can rule out #2, then it's definitely time to give TW a call since #1 and 3 can't be fixed on my end.
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