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8. Out of curiousity...

Well, not all of them will look the same, but here in Gainesville, if the node is on the ground, it's hidden inside this:



See the second box in the background? That one contains the battery backup for the node. I didn't have a chance to take pictures of the batteries, but just imagine 4 or 5 car batteries inside that box and that's kind of what it looks like. ;)

This is the inside of the node box:


This is a picture of a node that TACSPEED posted in the forums a few weeks ago:


by Raydr See Profile
last modified: 2002-11-06 01:13:16

That's a filter.

Feedback received on this FAQ entry:
  • we use step attenuators to control the upstream level , for example if your modem is at a 40 db upstream, we would add a 6 to 9 db attenuator to to bring that modem to a 46 or 49 . some filters are used for mitigation on noise and will only let 5 through 13 mhz to pass. (only put on tv legs NOT internet legs as it will block the upstream)

    2011-07-26 22:56:47

  • Yes, there are little round plastic fittings that go around the terminator. and you need a special tool to get up inside them to release the terminator by removing the plastic fitting/terminator at the same time. Now...if you need to open it and the cable co. won't care...just get a small pliers or something with a strong cutting tip to cut that "anti theft" part off. And the you will need a terminator tool (you can buy them everywhere) Ur just grab onto it with a LARGE pliers and give it a little crush. This will make the terminator spin (not so freely) and you can screw it off.

    2010-11-04 03:37:55

  • i have a weird cyliner thing on my splitter, but it looks more like a lock to prevent me from unscrewing the cable formthe splitter. this would prevent me from moving my connection.

    2010-02-12 11:35:53

  • what does the filter do ? do i need the filter to have a clear tv picture ?

    2008-03-20 06:15:00 (slckusr See Profile)



by Raydr See Profile
last modified: 2004-03-26 11:13:06

As far as the -15 to +15 range goes, that's not actually mandatory for the modem to work. It's the ideal range, because in most cases, at -15 the noise is starting to get bad.

Here's an analogy:
Say you're in a filled room having a conversation with someone. The volume they are speaking at will be the signal level. The volume of the people around you is the noise level.

Now, if the person speaking to you is at a low volume, you're going to have a hard time making out what they're saying because of all the noise.

HOWEVER, remove that noise from around you, and you can hear that guy just fine. If you have very little noise, you can operate at lower signal levels reliably.

I've had a modem running at -32db before, because it was running through a 300MHz splitter.

Feedback received on this FAQ entry:
  • The best signal for a modem to run on is 0db, we here the specs for operational signal is between -10 and +6db. Upstream 51db is the max and 33db is the min. Then snr has to fall between 31db and 39db. I would say your modem which is at over 10db is running too hot. And your upstream power level is also a bit high for having such high downstream level.

    2008-12-06 03:50:26



by Raydr See Profile

I think there is a Node at the pole in my back yard. Do you get better results the closer you are to the node?

Not necessarily. The farther away you are, there is a greater chance of noise getting into the line, but the difference in speed is quite negligible, especially since the LEs (Line Extenders, or amplifiers) boost signal both ways all the way down the line.

Feedback received on this FAQ entry:
  • If there is noise in the line feeding the node, then no matter how close or far away you are from the noise, it still all hits the node at the same time, a phenomenon called the Funnel Effect. Distance from the node truly doesn't matter.

    2009-10-18 11:24:43



by nwilcox See Profile edited by ergibbs See Profile
last modified: 2003-04-17 09:07:49

Yes, there is an optimal range for every class and type of service, every operating system, etc.

Go here:

»/tweaks/

Thanks to StillLearn See Profile for pointing out a spelling mistake.

by Raydr See Profile
last modified: 2005-05-17 10:13:59

You can never have too much protection. Lightning can enter your home through your cable lines just as easily as the phone/electric lines. Of course, the NEC requires that we ground the line to prevent lightning damage, but that does not guarantee that lightning will not enter your home.

I recommend a surge protector for your cable modem if you're in an area with lightning storms (especially in the south). Make sure you get one that is cable modem compatible.

A surge protector shouldn't affect bandwidth. From what I've found, it will either work or it won't. Make sure you use a surge protector that is rated for cable and/or DSL modems.

Feedback received on this FAQ entry:
  • Be VERY particular about the surge protector you buy! I have seen too many as a cable tech that simply eat the signal alive. I don't mean a small level reduction, I'm talking good signal going in and utter garbage coming out. The cheap no-names are always a bad bet, but spending a lot of money isn't a guarantee of quality. I've seen Monster surge protectors that are just as bad as the no-names (go ahead and sue me Monster, I don't care). In my personal experience as a home theater installer I've found Panamax to be of excellent quality. You don't have to spend a metric ton on them to get a good product either. That's just my personal experience, so don't take it as gospel. Just remember that if a cable tech comes out to fix a problem and sees a surge protector in-line they'll most likely tell you to leave it out. It's still the safest bet for signal quality.

    2009-09-13 11:06:45

  • Responsibility to properly ground the system belongs to the installer which may have been some bloke the cable company hired to do the work instead of themselves. If you are in the USA, you can contact the code enforcement office of your local municipality to find out what is standard procedure for your area. You would also probably have to prove the installer didn't install proper grounding initially and then have to locate them. It would be faster to file a claim on your home owners insurance.

    2009-07-25 22:04:11 (rjhawkin See Profile)

  • Can you tell me if the cable company is responsible for damages...Recently, our cable internet service quit working. After calling the cable company out, I was told that lightening had got my cable modem. I asked how that happened since I had my pc on a surge protector and was told that the cable line itself was not plugged into a surge protector. I had no idea I could or should have done so. Anyway, later that day I realized that my sons new television - which had cable directly plugged into the back, as well as my new DVD/VCR player-which also had the cable line plugged directly into the back-no longer worked. They won't turn on at all. My son had a lamp plugged into the same electrical outlet as his tv and my television that was connected to my DVD player still works. So, basically everything that the cable line was plugged into stopped working. I called the cable company again & asked about my cable line being grounded. The service man went by my house & sure enough said it was not grounded. He tried to tell me that I didn't have a ground under my power meter. I really don't know that much about this kind of thing, but he then went on to say there was a ground wire from my telephone line (which I don't use???) and he hooked the cable line outside up to the telephone ground. He said, "someone must have disconnected it." I live with my 11 yr. old son & my 21 yr. old daughter and I know for a fact that no one has disconnected any kind of wiring...ever. Is the cable company responsible for my damages? Should they not have ensured that my cable was grounded when they installed it? I'm not sure how to check this website. If anyone can help me with this question, my email address is lisamarie329@hotmail.com

    2008-04-29 20:59:23

  • But please make sure you do not hook the coax line itself up to the surge.. This typically causes noise in your return path and sometimes Interactive Services may not work. More than once I pull the STB out take levels and see perfect levels. Take levels at the wall plate and no difference.. So your getting ready to the box or modem out and you see the strip unplug coax from strip and go straight wall to box and POOF! it all works again..

    2008-01-06 00:45:19 (GoingUp22 See Profile)



by gahan See Profile edited by ergibbs See Profile
last modified: 2003-08-18 13:31:39

Check out this FAQ for a detailed description

by StillLearn See Profile edited by ergibbs See Profile
last modified: 2003-08-18 13:24:09