How do I can delete the noise in ADSL line

Discussion in 'General Electronics Chat' started by Mans, Oct 3, 2012.

  1. Mans

    Thread Starter New Member

    Oct 1, 2012
    12
    0
    My ADSL speed is lower than what the server has defined. They told there is a noise in my telephone line. Is there any circuit for deleting this noise ?
     
  2. kubeek

    AAC Fanatic!

    Sep 20, 2005
    4,670
    804
    I don't think so.
     
  3. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    4,769
    969
    dsl line filters are like $10 at the stores.. The company that installed the DSL should have put one on the phone line..
     
  4. W4GNS

    Member

    Dec 1, 2008
    17
    2
    I would tell them to fix it! You're paying good money for that service. As Mcgyvr states, a filter should have been installed by the tech when installed.
     
  5. bertus

    Administrator

    Apr 5, 2008
    15,647
    2,346
    Hello,

    The splitter/filter should be installed in the ADSL line.
    The actual speed can be dependend on the distance from the connection point to your home.
    I have a 20 Mb line and have a actual speed of about 18 Mb.
    (and I am pretty close to the connection point).

    Bertus
     
  6. vk6zgo

    Active Member

    Jul 21, 2012
    677
    85
    If you do have noise,you may find your ADSL provider is trying to "pass the buck" to the Telephone Company.
    If it is a dual POTs & ADSL service,do you hear noise on the phone?
     
  7. crutschow

    Expert

    Mar 14, 2008
    13,003
    3,232
    The DSL filter is mainly to filter out the DSL signal from the telephone so you don't hear a hiss in the telephone.

    If there's troublesome noise on the line it's likely at a frequency near the DSL frequency and can't be filtered. You might try running a direct line from your phone box outside to the DSL Modem, if possible.
     
  8. bertus

    Administrator

    Apr 5, 2008
    15,647
    2,346
    Hello,

    Here is a little drawing from my old ADSL modem manual:

    [​IMG]

    As you can see there are NO phones connected before the splitter.

    Bertus
     
  9. vk6zgo

    Active Member

    Jul 21, 2012
    677
    85
    The last time I had noise on my line,it was broadband,& audible on my phone.
    This was good,as it allowed me to bypass the ISP & talk directly to the Phone Company,who fixed it straight away.

    The protocol & "duckshoving" between the ISP & Phone Company can be a major pain in the butt when the fault only appears on ADSL.
     
  10. dataman19

    Member

    Dec 26, 2009
    136
    29
    So the IS says you have "noise"? What kinda noise" Can you hear it in the telephone (just dial any number and listen.....???
    ..
    Incidentally, DSL is highly susceptible to cross connects. DSL lines are also highly susceptible to "adjacent T-1 data lines" - which is why T-1 Data lines are supposed to be physically separated and even routed over separate trunk cables, etc.
    ...
    My method of troubleshooting would be to put a telephone on line (with the DSL filter installed in-line with the phone). Go to the DEMARC (the place where your phone lines come into the house/apt or building). Unplug the house (it's the phone plug that is accessible when you open the cover). Plus the phone with the DSL line filter into the Phone line (if you plug it into the right jack, you should hear a dial tone, if not - you have the wrong jack). Dial a 1 and listen. If you hear noise - the phone company is probably at fault - call them and tell them they are messing up your DSL.
    ..
    If you do not hear noise, reset everything back the way it was. This time plug the phone with the DSL Line filter into the phone line output jack on the DSL modem (most have a line In and Line out - the Line out being the phone line to the house phones. Note this is not always used, but it is a place to do the listening test). Dial 1 and listen, do you hear noise? Yes - then unplug the DSL Modem. Still hear noise? Yes -= you are back to square one (I would once again call the phone company).
    ..
    But there is one last test (I had assumed you had already done this one - so excuse me for listing it now. Just want to cover "all bases"). Plug the phone into any working phone jack in the house (preferably the one you already use it at - make sure the DSL In-Line Line filter is installed in-line with the phone. Dial a 1 and listen. Hear noise? Yes - Go to the DSL Modem and unplug it (power it down). Still hear noise? Yes - you probably have a cross connect or asymetrical phone pair - this is a Phone Company fix - You will have to call the phone company.
    ..
    So you ask - How can have an asymetrical phone line? I didn't have one before? The answer is simple - but may **** you off. Sometimes when a phone company installer is installing someones phone they will get a pair ssignment that doesn't work. Maybe because they have a non standard cross connect that interconnects one of the wires with an adjacent phone line (your phone line). he easy fix is to get another pair - but the phone company may not have another pair that will reach the new customer. But they just may have a new pair that will reach you - so the lineman changes your pair for the new pair. The new customers phone works, and you still have service - a win-win? Maybe, Maybe not. Suppose the new pair given to you has a cross connect to another box across town (a common occurrence if "other" installers didn't take down the "old" cross connects - which "they are supposed to do - but more often than not - DON't". So pow you have a phone line with a non-standard loading and non symetrical pair loading - which DSL hates and sees as noise "hidden noise or audible" to DSL noise be noise. DSL cannot function with too much lnon symetrical loading and any non symetrical loading causes the DSL performance to drop radically. This is the trait that we loved about DSL when we were installing DSL links to STUII (Secure Telephone Units) units for US Embassy's all over the world in the late 1970's - the fact that a wiretap would cause the DSL to load and the insecure link to advise that the line was compromised. Then in the 1980's our dear old government decided to license the technology and GTE bought it and branded it DSL (Digital Subscriber Line) service.
    ...
    Long story - but possibly explains what may very well be happening. If you have noise on the phone line - it is a phone company problem. The only way to prove it is to test at the DEMARC. If you essentially unplug the house and the line coming from the Phone company has noise - it is "their problem". If you unplug the house and do not have the noise - it is in your house wiring or equipment. The next logical step is to unplug all the phones, and test again with only one phone. If you still have noise in the house, unplug the DSL Modem. If it clears up - Your DSL Modem is defective.
    ..
    Oh yea, don't forget to eliminate the possibility that you may have selected the "Very culprit that is causing the problem - the one faulty phone to test with" - so eliminate this by retesting with another phone.
    ..
    Me I would just get out one of my HP3555B Telephone test sets and test the line. Then when I talk to the phone tech I can actually tell them the symptoms, etc. Trust me. sometimes they get snotty, but they always show up real fast to fix "their problem". I still have a lot of my old gear, both analog and digital - so when I tell them I have "line imbalance" or "non-symetrical paid dynamics" I can prove it (and they know I can). Plus I have the cell phone number for the Telephone Company's chief plant engineer in Phoenix, AZ, Tuscon, AZ, Yuma, AZ, Oklahoma City, OK, Atlanta, Ga, Warner Robbins, Ga, Cordelle, Ga, Valdosta, Ga, Albany, Ga, Nashville, Tn, Memphis, Tn, Chattanooga, Tn, Miami, Fla, and Knoxville, Tn. Trust me, I can get their attention real quick. I might be retired, but I can still "use" a telephone.
    ..
    In either case - I hope I have at least given you a few pointers to actually help resolve your issue. Just one more word - Not all line noise is audible. If as a last resort you move the DSL Modem and Computer to where you can eliminate the house wiring by unplugging the house and plugging directly into the incoming phone line - you should get a "drastic increase in DSL speed" if you do, you have an internal problem for sure. But if you see no improvement in DSL speed (in other words it is still crappy - "you did say it has drastically dropped recently?") - then the Phone Company needs to fix it.
    ...
    Dave
    Phoenix, AZ
     
  11. Mans

    Thread Starter New Member

    Oct 1, 2012
    12
    0
    No, it is normal
     
  12. Mans

    Thread Starter New Member

    Oct 1, 2012
    12
    0
    This is what the sever employees recommended me. They said I install a separate line from the phone box to splutter. It is possible but I am not gay to do that and am interested to find a filter circuit instead. Also the phone voice hasn't any noise. I found this circuit in a website, is it effective ? Also how do I make the coils?



    [​IMG]
     
  13. kubeek

    AAC Fanatic!

    Sep 20, 2005
    4,670
    804
    That circuit is intended for phone, not adsl, and the only thing it could do is stop the adsl from working alltogether.
    What that circuit does is that it filters anything above 20khz, which is where the dsl traffic is located.

    Anyway, ADSL technology is very sensitive to the quality and length of the phone line between your socket and the switchboard, also most operators call anything above 1/2 of the speed you pay for ok.
     
  14. DMahalko

    Senior Member

    Oct 5, 2008
    175
    14
    In general phone lines run inside buildings are only intended for voice in the 1 kilohertz range, and are crappy unshielded non-twisted-pair "Category 3" cable.

    For the best possible DSL signal, you need replace all your house wiring with at least Category 5 UTP (unshielded twisted pair) to greatly improve the signal quality.



    Probably this is too complex and expensive to do, so the next best option is:

    1. Install a single DSL filter in/at the gray telco box where the signal feeds into your house. This will cut off DSL from using any CAT-3 lines.

    2. Next from the gray telco box, wire a separate single Category 5 UTP that goes only and directly to the DSL modem and nowhere else.

    3. Install a grounded lightning surge protector between your DSL modem and the phone line. DSL modems can experience a loss of speed over time due to voltage spikes induced in the phone lines from nearby lightning strikes. It does not require a direct lightning strike to damage a DSL modem.

    This is how I have my DSL wired.



    The line in the ground from the road to the house is often a multi-pair trunk cable with a shield, but if your incoming house telco box is tiny one-piece thing about 4"x"4x1", and does not have the two split doors (one for technician, one for homeowner) then the grounding is probably also weak or bad.

    Most telcos want to know about the old house telco boxes, to replace and upgrade them and put in better trunk line grounding, plus also install a loop test doodad so they don't need to do a truck roll to test the line in the future.



    Finally, phone lines were not made for high frequencies but only for a narrow voice frequency band in about the 1 kilohertz range.

    DSL is basically like playing classical music and listening to it through a garden hose. If you use a short five-foot hose, then it'll still be mostly high fidelity, but if you're using 200 ft of garden hose, you'll just hear a muddled mess. The speed of DSL declines over distance for similar reasons, because telco lines can only do high quality for a short distance.



    It is possible to improve DSL signal distance, by installing an amplifier between you and the telco, but since this involves modifying phone trunk lines, only the telco is able and authorized to do it.

    This doodad is called an "ADSL Loop Extender" and only telcos buy and install them.

    http://en.wikipedia.org/wiki/ADSL_loop_extender

    I suppose it might be possible to offer to buy one for your telco to install on your line, to improve signal quality, but I've never heard of this being done.



    It is also possible to increase signal distance by properly balancing the trunk line with "loading coils". Again, only a telco can install these.

    http://en.wikipedia.org/wiki/Loading_coil

    Loading coils have been used on phone lines for decades but were originally intended to extend voice-only quality, and not caring about the high frequencies that DSL uses. There are now companies making newer types of DSL-compatible coils with a better attuned signal profile to get DSL further down the trunk line.

    For example, Charles Industries "Smart Coils":
    http://www.charlesindustries.com/main/te_smart_coil.html

    Most DSL speed drops out around 15000 ft (2.8 miles), but Charles says their Smart Coils can push DSL to up to 24000 ft (4.5 miles).

    Though it's extra expense on the part of a telco to buy and install these, so they may not want to do it, just looking at their bottom line costs per potential customer. I have no idea if you can offer to buy one for the telco to try to improve your line speed.
     
    Last edited: Oct 4, 2012
  15. dataman19

    Member

    Dec 26, 2009
    136
    29
    Mans
    That circuit will load the line and "kill" your DSL.
    ...
    The best advice offered so far was the one where you should just install a DSL Blocking Filter at the gray DEMARC Box. But - Then you have to split the phone line there (No problem, just get five Radio Shack Phone junction boxes. You will also need a Cat5e or Cat6 data cable (if your DSL Modem has an RJ45 Port for both the Data Out and Telco In ports - great. The Data cable will already be terminated - you just need to find out which pairs in the dtat cable correspond with your DSL Telco Input (usually the blue/white pair, - but confirm it). On the first Telephone Terminal Block, wire the red and green phone pairs to the Gray DEMARC red and Green Wires (hint Red and Green are the phone Tip and Ring - the phone lines). Jumper the red and green terminals to a second Junction Box and use the red and green terminals there too. This will result in one phone line coming in and going to two phone boxes with the RJ11 (phoen connectors).
    ..
    Now wire the house phones to a third Phone Junction box (use the red and green terminals on this as well). Now plug the DSL Line filter into one of the original two paralleled (they both have the red and green terminals wired to each other with the original red and green wires coming from the Gray DEMARC Box). This will give you a DSL free phone lines into the house.
    ..
    Now you need to get DSL to the DSL Modem.
    ..
    Wire a new phone line to the fourth telephone terminal block (hooking the wire up to the Red and Green Terminals) NOTE: When you go to buy the telephone wire - DO NOT buy Telephone Wire. As stated earlier - get the Cat5e or Cat6 wire - it works better with DSL signals. Since you have installed the DSL blocking filters and you are going to hook up the DSL through the new line, which will be data cable - your DSL will work better).
    But first you have to run the new Data Capable phone line to the DSL Router - so you will need another Radio Shack Telephone Terminal box to place at the DSL Router - or just put a telephone cable end on that matches your router (My routers have Cat5 RJ45 connectors on both the Telco and Data Ports - makes it a lot simpler). Anyway, once you get the DSL router hooked up - fire it up.
    ..
    Now check your DSL speeds. Should be better.
    ..
    Oh yea. If possible, put the DSL router close to the Gray Telco DEMARC. It will eliminate any possibility of the data line loading (since the DSL blocking filter will eliminate the telephone lines from loading the DSL - eliminating any added cabling between where you put the filters and the DSL modem will only go to improve the signal quality. Beside, Ethernet has like a 1,000 meter or so distance limitation - I am assuming you aren't going more than that distance to the computer(s), are you?
    ...
    OK here are some links:
    ...
    http://www.homephonewiring.com/
    ...
    Now about that DSL lines:::
    ..
    http://www.homephonewiring.com/dsl.html
    ...
    Wiring a DSL Splitter (Note: some router/Modems have a Telco Input Port, a Telephone Line Out Port and a Data Out Port - these should be considered DSL Splitters for the sake of how the the second link is diagrammed).
    ..
    Here is the HomeTech Wiki:
    ...
    http://wiki.hometech.com/tiki-index.php?page=DSL+Installation+Tutorial
    ...
    Here are the color codes to connect a cat5 cable to a phone cable (to get DSL to the router/modem):
    ..
    http://www.ask-the-electrician.com/Pics_Phones/phone wiring drawing_ED2.JPG
    ...
    This is what that Radio Shack Phone Terminal looks like (with cover off). Note: The terminals have (R), (G), (B) and (Y) lables to keep you from getting lost.
    ...
    http://0.tqn.com/d/electrical/1/0/K/4/-/-/wire-phone-jack-400.jpg
    ...
    Here is a really long article (worth reviewing - but don't get bogged down):
    ...
    http://archive.arstechnica.com/guide/networking/installation-1.html
    ...
    Here is another good info page:
    ...
    http://www.dslreports.com/faq/faq/8._Home_wiring
    ..
    This list can go forever...
    ....
    I think you get the point by now.
    ,,,
    Dave
    Phoenix, AZ
     
  16. westom

    Member

    Nov 25, 2009
    52
    5
    I am completely confused by your questions. Somebody said you have too much noise? That alone is sufficient to *know* you have too much noise?

    If noise exists, you (or he) also have a number. Obtained directly from a server inside your DSL modem. The all so important dB number is necessary long before fixing or even accusing anything. What is that number?

    Typically connect to the DSL server using a URL of 192.168.1.1 . Long before solving a problem, first that problem must be defined. That means numbers.
     
Loading...