TLC is corrupt and pixelized on Comcast via cablecard

[MickBurke]

My wife's favorite channel is TLC, and for some time now, ANYTHIGN on TLC is pixelated and garbled when recorded or played through sage. If I watch on the 'box' it works fine (maybe an occasional glitch?), but everything on sage from TLC is a mess. Any ideas what might be doing this? There's no other channel that does it, and again, most of her shows are on that channel. I also checked the alternative channel for TLC (1450 I think).

[UgaData]

Over time, I have had certain channels that for some reason don't play well when tuned by a specific tuner. What I have done is to create a separate channel line-up for just that tuner and remove the channel it doesn't seem to tune very well.

I will fully admit it doesn't make any sense but it does seem to work.

F.W.I.W. - I have a Ceton ETH6 tuner and Comcast.

First however, you may want to double check cable connection, how many splits the cable has before getting to the tuner, etc.

[wayner]

Originally Posted by MickBurke

My wife's favorite channel is TLC, and for some time now, ANYTHIGN on TLC is pixelated and garbled when recorded or played through sage. If I watch on the 'box' it works fine (maybe an occasional glitch?), but everything on sage from TLC is a mess. Any ideas what might be doing this? There's no other channel that does it, and again, most of her shows are on that channel. I also checked the alternative channel for TLC (1450 I think).

What's your tuner/encoder and if you have more than one tuner/encoder does this happen with all of them?

[MickBurke]

Sorry! Cant imagine why I didn't think to share that basic info!
I have a CETON Infinitv 6 tuner network box.
I did check each of the tuners that it has (all six) and they do all do the same thing.
Also using OpenDCT ...

[KeithAbbott]

I was having issues with certain channels being pixelated awhile back. I would take a look at what splitters, etc. that you have between the cable coming into the house and your Ceton device. That channel (TLC) may have low signal strength. I posted this back in October: https://forums.sagetv.com/forums/showthread.php?t=66540

[JustFred]

Originally Posted by MickBurke

I have a CETON Infinitv 6 tuner network box.
I did check each of the tuners that it has (all six) and they do all do the same thing.

Is both the set-top box and Ceton card connected to the same run of coax from the demarc? If not, temporarily connect the STB and Ceton to the same coax run to see if they both behave poorly.

Pixelization is most frequently caused by poor (RF) signal quality. Ingress from nearby cell towers is often contributory. Any splitters (especially those outside the house) that show any signs of corrosion should be replaced. The increased humidity of winter can wreak havoc with poor connections. Check that all coax cable connectors throughout the entire house are screwed on tightly. Also verify that all connected (but unused) coax cables have a terminator installed.

[wayner]

A few things to try:
Can you determine the signal level? I have one cable box that had a very low signal to noise ratio which was causing the file to be corrupted.
Can you play back the file in other software like VLC of MPC?
If the answer to the above question is yes then you might want to try something like VideoReDo to fix the file. Kind of a pain in the butt however, unless you can automate it with SJQ.

[mechling-burgh]

I know when I had problems with Comcast in the past you could call in I believe and rest the card. This fixed my problem sometimes.

[MickBurke]

Originally Posted by KeithAbbott

I was having issues with certain channels being pixelated awhile back. I would take a look at what splitters, etc. that you have between the cable coming into the house and your Ceton device. That channel (TLC) may have low signal strength. I posted this back in October: https://forums.sagetv.com/forums/showthread.php?t=66540

Cable guy ran new lines when he setup, so I figured we were OK there, but I'll give it another look!

[MickBurke]

Originally Posted by JustFred

Is both the set-top box and Ceton card connected to the same run of coax from the demarc? If not, temporarily connect the STB and Ceton to the same coax run to see if they both behave poorly.

Pixelization is most frequently caused by poor (RF) signal quality. Ingress from nearby cell towers is often contributory. Any splitters (especially those outside the house) that show any signs of corrosion should be replaced. The increased humidity of winter can wreak havoc with poor connections. Check that all coax cable connectors throughout the entire house are screwed on tightly. Also verify that all connected (but unused) coax cables have a terminator installed.

We've got the run from the outside comes through the wall into a three way splitter then out to the cable modem, the tuner, and the 'cable box' as us old heads call them. I think I may try swapping out the lines to the modem and the tuner... Thanks!

[MickBurke]

Originally Posted by wayner

A few things to try:
Can you determine the signal level? I have one cable box that had a very low signal to noise ratio which was causing the file to be corrupted.
Can you play back the file in other software like VLC of MPC?
If the answer to the above question is yes then you might want to try something like VideoReDo to fix the file. Kind of a pain in the butt however, unless you can automate it with SJQ.

Sage shows 100% signal, but I think it always does when you have any signal.
I got into the infinitv management web page and it shows Signal Level of -7.5dBmV and S/N% 37.4dB
A solid channel picked at random shows Signal of (+) .4dBmV S/N of 39.0dB
I also found that the two channels around it are problematic as well, and they show Signal -7.6dBmV and S/N 37.6
One past that, which does work OK, shows -5.3 and 38.3 respectively.
So it may be that extra -2 that is causing the problem.
I'm going to try to swap out cables to the tuner I think! Thanks!

[MickBurke]

Originally Posted by mechling-burgh

I know when I had problems with Comcast in the past you could call in I believe and rest the card. This fixed my problem sometimes.

I went thorough SO much to get this set I wouldn't dare! Had to go through 3 installs and 5 different cable cards to get it working!

I DO appreciate the suggestion though!

[KeithAbbott]

Originally Posted by MickBurke

We've got the run from the outside comes through the wall into a three way splitter then out to the cable modem, the tuner, and the 'cable box' as us old heads call them. I think I may try swapping out the lines to the modem and the tuner... Thanks!

I would try an experiment, replace the three-way splitter with a two-way splitter, connecting just the cable modem and the tuner. If that reduces or eliminates the problem, you might have found the cause. A three-way splitter will result in signal loss of 7dB, a two-way splitter only results in a signal loss of 3.5dB.

[MickBurke]

Originally Posted by KeithAbbott

I would try an experiment, replace the three-way splitter with a two-way splitter, connecting just the cable modem and the tuner. If that reduces or eliminates the problem, you might have found the cause. A three-way splitter will result in signal loss of 7dB, a two-way splitter only results in a signal loss of 3.5dB.

Great info, thanks!

If I find that to be the case, is there any way to boost the signal? Any other options?

[KeithAbbott]

Originally Posted by MickBurke

Great info, thanks!

If I find that to be the case, is there any way to boost the signal? Any other options?

Assuming that your cable provider has set the proper signal level coming in to your home, the only other option that I am aware of is using a coax amplifier. But the amplifier should not be upstream from your cable modem. So you would use a two-way splitter upstream from your modem, one leg after the splitter would go to the modem, the other leg to the coax amplifier. The outputs of the coax amplifier would go to your Ceton, and to your cable box. The device that I mentioned in my other post has everything combined into a single device.

[JustFred]

Originally Posted by MickBurke

Sage shows 100% signal, but I think it always does when you have any signal.
I got into the infinitv management web page and it shows Signal Level of -7.5dBmV and S/N% 37.4dB
A solid channel picked at random shows Signal of (+) .4dBmV S/N of 39.0dB
I also found that the two channels around it are problematic as well, and they show Signal -7.6dBmV and S/N 37.6
One past that, which does work OK, shows -5.3 and 38.3 respectively.
So it may be that extra -2 that is causing the problem.

Those signal levels are plenty strong. For reference, your cable modem wants somewhere between -10 dBmV and +10 dBmV, but it will usually work correctly within the range of +-15 dBmV. The requirements for a good video signal are generally even looser than that.

Those S/N numbers *seem* pretty good, too. The cable modem generally needs > 30 db S/N for reliable data transfer. TVs, STBs and Ceton tend to work well with even less.

When comparing signal levels of "adjacent" channels, remember that the Guide numbers on a CATV system often have no obvious correlation with the RF frequency that carries them. Looking closely at the Ceton mgmt pages will give that info.

[MickBurke]

Originally Posted by KeithAbbott

Assuming that your cable provider has set the proper signal level coming in to your home, the only other option that I am aware of is using a coax amplifier. But the amplifier should not be upstream from your cable modem. So you would use a two-way splitter upstream from your modem, one leg after the splitter would go to the modem, the other leg to the coax amplifier. The outputs of the coax amplifier would go to your Ceton, and to your cable box. The device that I mentioned in my other post has everything combined into a single device.

Thanks! I completely missed the link somehow!

[MickBurke]

Originally Posted by KeithAbbott

The device that I mentioned in my other post has everything combined into a single device.

I remembered I had something similar from a project a few years back. But I'm guessing I'd need to split before this to feed the modem as you had mentioned previously?


https://photos.app.goo.gl/msKLM3UeDa2u9eSW7

[wayner]

For what it is worth, I have one of those and I split the incoming cable before feeding my cable modem (for internet) and cable boxes that I use with HD-PVRs feeding into SageTV.

So the feed goes:

Cable from outside ---- Splitter -------------Cable modem
                                          \-------Cable box
                                          \-------Cable box
                                          \-------Cable box

[MickBurke]

Originally Posted by wayner

For what it is worth, I have one of those and I split the incoming cable before feeding my cable modem (for internet) and cable boxes that I use with HD-PVRs feeding into SageTV.

So the feed goes:

Cable from outside ---- Splitter -------------Cable modem
                                          \-------Cable box
                                          \-------Cable box
                                          \-------Cable box

Thanks much!