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ADSL + PSTN over the same CAT5 cables 1

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Chris303

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Sep 17, 2006
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Is it possible to run 2 ADSL connections and 1 PSTN connection over 2 CAT5 cables? I am under the impression that ADSL requires just 3 pairs? and PSTN needs 2 pairs? so I should be able to use 8 the pairs for this purpose?

Chris
 
a pair is two conductors

by adsl if you mean ethernet then it will run on two pair (4 conductors )

a pots line will run on a pair (two conductors .)

so you could run them off one 4 pair but ist not advisable.


since you have two cat 5 cables run your pots line over one and use the second one for ethernet .





 
No I dont mean ethernet.

Where the line comes into the home I want to split PSTN and ADSL signal coming in and send them off independantly.

Chris
 
You will need an ADSL filter then. The filter has an input for the PSTN (POTS) line that has the ADSL on it. Then there are two outputs, one for the POTS line and the other for the ADSL. Not sure where you are or where you can get one of those filters.

Good Luck.


**************************************
My Biggest problem is that I almost always believe what I tell myself.
 
Yeah I know bout filters lol.... I want to take the outputs out each side of the filter and send them through a cat5 cable(s) - this is what I am asking about.

Chris
 
They should work just fine. Make sure you mark which pair is which so no one gets confused later, since they will both have DialTone...

Hope this helps!

....JIM....
 
are you trying to send the unfiltered dsl signal to two separate desktops ?

wont work

send it to a router then ethernet to your desktops


honestly you know so little about whats involved that you really ought to hire someone to set it up for you .
 
skip... when did I say that?

I work for ADSL technical support for a living so I know fine well I cant send a dsl signal to seperate desktops.

I have a comms cabinet which is where my router and ADSL modems will be located, but I want to split the signals at the master socket and send independantly to the comms cabinet where they wull be patched to the appropriate function (router / failsafe for voip).

You dont appear to be listening to what I have said skip, so I dont apreciate the comment above.

My question was

>>Is it possible to run 2 ADSL connections and 1 PSTN
>>connection over 2 CAT5 cables? I am under the impression
>>that ADSL requires just 3 pairs? and PSTN needs 2 pairs?
>>so I should be able to use 8 the pairs for this purpose?

Which is straight forwardly asking if I can send ADSL signals (unfiltered) and PSTN signals (filtered) up the CAT5 medium together without any problems (crosstalk etc)
 
you work for a adsl tech support [wink]

and you ask such basic questions and call pots lines pstn ...

have pair counts wrong ...

to answer your question , you can send filterd and unfilterd over the same cable , dosnt need to be cat 5, 3 will work just fine . we do it all the time

 
First, ADSL uses 1 pair, as does a 1MB (POTS). ADSL is usually piggybacked on an existing 1MB, using a higher frequency signal than analog telephone service uses (1.2MHz fr the former and 3.4 kHz for the latter).

If you split the signal early, you can certainly allow them to use the same CAT5 cable, as there is not a concern with interference. In fact, on a single 4 pair cable (CAT5, CAT5e, CAT6, CAT3, or whatever) you can carry 2 ADSL and 2 1MB.

I am guessing that the desired result here is to split the signal early, so that you don't have to filter every telephone in your house.

-Brian-
Semper Paratus
 
actually I think I talked to the op today , customer was having dsl issues so we called tech support

tech support guy was insisting that the unfiltred dialtone from the wall went to a RJ45 connector on the modem / router

I did point out that the modem had a rj11 marked dsl in and color coded to match the supplied rjll cord and that that was what we used , also told hem the DSL synch light was on but he kept insisting that we where plugged in wrong and that it should be a rj45 connection.

(we accidntly hung up on himn and called back in and got a diffrent support person )
 
lol.... im not like that skip...

I call a analogue line a PSTN line because thats what I am used to, and thats what BT wholesale call them in communication with us.

Jedi... I want to filter as early as possible to achieve a better SNR. It has been proven that sending the ring wire (intoduced at the master socket) along with the ADSL signal to extension sockets much greater noise is introduced as a ring wire circuit round your house will effectively serve as a big antenna picking up all sorts of crap onto the wires.

Other people achieve this similarly by just disconnecting the ring wire to their extension sockets, which wont affect the telephones in use as their filters will introduce a ring current to the telephones in question.
 
If you install your filter for the phones at the protector/demarc, that should work the best. All the filters I have seen are balanced H low bandpass types. Since the loop is a balanced two wire medium you want to keep it in balance. Opening the Ring can cause it to be unbalanced and induce more noise problems.

....JIM....
 
SYQUEST.... things are different here in the UK. we dont have a "demarkation point" as such like you do in the states (i assume thats where you are), but what you are talking about is essentially what I am doing.

UK lines with British Telecom "demark" as you call it at an actual telephone socket in the premises called the master socket.

This master socket is known as a NTE5 socket in which I have fitted this face plate to the front of it, which gives you punch down terminals for both your telephone extension wiring, and also for ADSL. (as well as front jacks which I will not be using).

 
Chris303,

Yes you can push the PSTN (POTS) line and the ADSL through cat5 cables.

Split the two with the usual filter, use an RJ11 - RJ11 cable to connect the ADSL output to the cat5 and a BT431A (BT Plug) - RJ11 cable to connect the PSTN (POTS) line.

As for running 2 through the same CAT5 cable, you can buy adaptors that allow a telephone and ethernet to be run over a single cat5 point (one at each end) which will allow you to run one adsl & line through one cable and the other ADSL line through another.

Only thing to watch out for is the length of the cabling.



Eric (UK Telecom's Veteran)

 
I am hard wiring cat5 cable straight into the NTE5 socket and as such dont have a requirement for any kinds of plugs (rj11/rj45/bt etc) - the cat5 wiring goes straight to my central patch panel.
 
OK.... But you said you wanted to split it at the NTE.
No problem. Just connect pins 2 & 5 of the NTE5 on the Blue/White - White/Blue pair, if the other end is connected to a patch panel you will need an RJ45 to BT Socket adaptor (secondary). Plug your filter into this otherwise use a secondary socket (without the capacitor). This is effectivley an extension socket, but without connecting pin 3 you will not extend the ring circuit and avoid the interference you mentioned in an earlier post.

Good luck

Eric (UK Telecom's Veteran)
 
why do I need a filter?

I already explained the NTE5 socket has a built in filter in the faceplate, which I can hardwire unfiltered and filtered signals. (see the link I posted above)

this is what I want to do.

NTE5 (unfiltered signal) --> CAT5 --> patch panel > DSL modem --> router --> patch panel --> CAT5 --> network port in room.

NTE5 (filterered signal with ring wire) --> CAT5 --> patch panel --> CAT5 --> phone port in room

Now on my CAT5 cable I obviously have 4 pairs. One pair I will use for the unfiltered signal, which does not have the ring wire. If I want to take the ring wire for the filtered signal then I am going to need to use 3 wires i.e 1+1/2 pairs.

From what I know of twisted pair technology it works by transmitting the inverse signal on the second wire of a pair, now how can I send 3 wires across 2 pairs without the 4th wire having any signal?

Additionally.... is the ring wire likely to affect the unfiltered signal on the *other* pair?

Hope that makes more sense.

Chris
 
Ok - see what your after now.

I assume there are 2 NTE's involved here

Are the cables you will connect at the socket connected to a patch panel in the cabinet?

Will the phone device be connected to a cat5 point elswhere in the building that appears back on a patch panel in the cabinet?

Eric (UK Telecom's Veteran)
 
no there is only one NTE5... my diagram was just expressing the two signals coming from it.

take a look at that link above.... its a front plate for the socket which gives you POTS as well as ADSL ports, plus extension terminals.

Chris
 
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