Upstream Power Level Too Low

[NUBETOOBER39]

Pretty much what the title says. My upstream power levels seem to be lower than the minimum spec for my modem wants and I would like some advice on how to fix it without having to bring in a tech. I still receive internet and connectivity, but the low power causes my connections to fluctuate a lot.

My modem is the Motorola Surfboard SB6183 http://arris.force.com/consumers/articles/General_FAQs/SB6183-Cable-Signal-Levels

It says that it requires a minimum of a 45dBmV power level, but my channels range from 32.4 to 35dBmV. All of my downstream power levels seem to be in a good zone between 5dBmV to 6dBmV, and they have wiggle room to be decreased to help the upstream.

I was thinking of adding an attenuator of some sort to help increase the upstream power level, but adding the amount I need would then decrease the downstream quite a bit (still in the spec of +/- 15dBmV, but still a large amount).

I just wanted advice as to how to go about this problem. I need to increase my upstream by about 13dBmV, but keep the downstream within the +/- 15dBmV range. Any ideas?

https://imgur.com/a/0yDUt

 

[bill001g]

What is your actual issue.

Not sure why they would have a recommended minimum level. The upstream power level is something that is controlled by the cable company equipment remotely. Based on how much signal they receive they tell your modem to increase or decrease its power.

A low upstream power number generally means the cable company equipment is receiving good signal levels from you. If they were receiving poor signal levels the equipment would have your cable modem increase its output levels. They want everyone transmitting at the very lowest level that still performs since it can cause issues for other people sharing the connection that have poor signal levels.

 

[NUBETOOBER39]

What is your actual issue.

Not sure why they would have a recommended minimum level. The upstream power level is something that is controlled by the cable company equipment remotely. Based on how much signal they receive they tell your modem to increase or decrease its power.

A low upstream power number generally means the cable company equipment is receiving good signal levels from you. If they were receiving poor signal levels the equipment would have your cable modem increase its output levels. They want everyone transmitting at the very lowest level that still performs since it can cause issues for other people sharing the connection that have poor signal levels.

From what I've read (and from what the tech support from my modem's manufacturer said), if the power level is too low, then it's not able to communicate with the CMTS as it should. If it's too high, it can damage it. My problem is that my signal is not stable. As the power level is borderline, I receive some information steadily, then it will drop and go up and drop and go up.

I've had this problem before and we had to get a tech in to fix it, but that was from a degraded wire that pretty much gave up. This one seems to be early stages of what that was.

 

[bcrudisill]

Right-o, low upstream power level is your issue (to answer bill001g's strange question). In fact, I am experiencing the same problem currently and, in fact, my modem's data looks nearly identical to what you posted. You should be able to contact tech support to have this problem addressed, but I've found the language barrier to be too much of a hassle. Fortunately, I already have a tech coming to my house in a couple of days to replace the tap on my street so that I can start receiving the upgraded internet speeds I'm paying for. I'm going to have them look at my upstream power levels at that time.

That said, if you can't get your problem across to tech support over the phone (they have a tendency to just want to keep rebooting the modem ad infinitum) then you will need to have a technician come to your home. If it's free, I'd suggest the latter anyways. They can make sure everything else is looking clean and updated as well. Good luck!

 

[andyb.ccvn]

That upstream power level is perfectly fine. Some cable systems (actually most) don't use exact specs on line equipment because in reality a system is going to have to operate based on outside forces like geography and topographic variables. They set up equipment based on what works for that area.
The upstream power level is essentially how hard your modem has to work to talk back out to the world.
Think of yourself as a modem in a crowded room of people (other modems). Do you want to have to scream at people at 51 dB or would you rather talk at 34 dB? Now, with lower levels, the amplifiers are generally running a little harder and this can create upstream noise. However, if the upstream SNR is within spec for the cable company, they're going to leave it where it is.
Just my 2 cents based on a decade of CATV line tech experience.