Sharer

Re: Intermittent T4 errors SB6141

agentx5, you're probably correct about that, at least till the next time something comes loose somewhere out there, and the problems return.  As you may remember, I had a thread going for over a year with my SB6141 issues.  Over the past few months, I swa the exact same issues as this poster describes, with T4 reboots,....only in  my case they were every two or four days for the most part.... and pixelation/breakup on some cable TV channels as well.

 

Bucket trucks were out a few times but it wasn't fixed.  Then  from October 11 through October 28, I had no T4 reboots at all, everything looked great except for rare TV pixelation.  I assumed the bucket truck guys found and fixed something.  

But then on October 28, boom..... T4 reboots came back and now occur every 3 or 4 days, along with occasional pixelation on cable TV.

 

I also monitor a neighbor's leased modem/gateway (16-channel) just a few houses downstream from me.  She does not have the issues.  I suspect the SB6141 is more susceptible to  outside line issues than other modems, based on my own experiences and numerous threads of similar issues all involving the SB6141.  It's a great modem as long as the street lines have no issues.

Proven Sharer

Re: Intermittent T4 errors SB6141

Pixelation on the cable TV viewing screen isn't caused by an issue within the internet service modem.  T4 errors are caused by a loss of signal from the head-end for an extended period - greater than 3 seconds.  That points to an external intermittent mechanical problem in the signal delivery chain, either a drop line or physical trunk line. 

Chances are that your neighbor a few doors down is connected into a different tap (and she's upstream from you) and the intermittent is probably located between her tap and yours.  After all, you've got grief, she's got signal without interruption.

Sharer

Re: Intermittent T4 errors SB6141

I never said the TV pixelation was caused by modem issues..... obviously it's not connected to the modem.  I stated that both symptoms, as described by the original poster, also occur here with my setup.  The pixelation is likely caused by interference in the lines on the street upstream from me.  My point being, that the TV pixelation is a sign of interference, and the SB6141 issues also relate to the same interference in the lines. 

I'm also aware of what a T4 error is ..... and the same problem in the signal delivery chain that causes the T4 can also affect the TV signal.

 

My neighbor a few doors down is not upstream from me, she is downstream.  Any trunk line issues that affect me would also affect her unless they were in my drop line..... and they are not.  The drop line has been changed twice, once by the bucket crew, along with every cable in & under my home and in the walls,  and when using a leased test 16-channel modem here, I too get signal without interruption.  I ONLY get drops and timeouts and reboots when using an SB6141..... have tested with 3 of them, two brand new white retail models (one HW v.7 and one v.8) and a black leased SB6141 from TWC.  They all have the same issues while three different 16-channel modems have no issues.

 

It's clear that the SB6141 does not handle line issues gracefully, and will drop signal in the face of too  much interference, while other modems do not.  That's the point of my comments and what I have demonstrated with a year and a half of continuous testing along with a bucket truck maintenance worker who has been on the issue with me for a year.  Robot Frustrated

Expert

Re: Intermittent T4 errors SB6141

try a 6183/90, the newer firmware/hardware in the DSP makes a big difference

 

Expert

Re: Intermittent T4 errors SB6141

When you use a Hauppauge tuner card or some cable ready TV's, changing channels on it will burp another cable box or modem causing pixellation and modem errors. Changing splitters  doesn't help. Only solution is to use an amp and attenuator as an isolator for the offending device.

Qam is very sensitive to Impedance change/ noise bumps, anything that changes the level or induces any sort of noise.