Phone over a CAT5 structured network

What's the accepted way of using your CAT5 network as telephone
extensions?

Last time i bodged it with two phone extention leads and replaced the
plug on one with an RJ45 and the socket on the other. This time round
i was thinking of getting BT to move the incoming line to node0.

I see you can buy 'RJ45 to BT' adaptors but this in only at the
extension end and i'd need to get the BT wires onto the right CAT5
wires. Is there a guide anywhere?

"anthony james" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> What's the accepted way of using your CAT5 network as telephone
> extensions?
>
> Last time i bodged it with two phone extention leads and replaced the
> plug on one with an RJ45 and the socket on the other. This time round
> i was thinking of getting BT to move the incoming line to node0.
>
> I see you can buy 'RJ45 to BT' adaptors but this in only at the
> extension end and i'd need to get the BT wires onto the right CAT5
> wires. Is there a guide anywhere?

Anthony,

I have a similar setup: Each room in our house has two cat5/RJ45 sockets which
run back to a patchpanel / Node0 in the study. The BT phoneline enters the
house at Node0 and lines are patched-in as required (The network is mainly
used for ethernet and there is a 16-port ethernet switch also patched in to
most rooms).

To make a pair of patch cables, I would take one standard phone extention
cable, cut it in two (to desired proportions), and fix an RJ45 onto each of
the severed ends making sure to wire the pins the same on both. One bit goes
from the BT phone socket to the patch panel, and the other bit is a phone
extension lead which plugs into an RJ45 socket. This setup seems to work with
no problems.

When I investigated this about a year ago, I couldn't find any wiring
standards on the internet for how the four (or six) wires of the phone cable
match up to the 8 pins of the RJ45. To buy a proper adapter was expensive, so
I didn't bother and just guessed. Although it would be nice to know if my
bodged 'RJ45 to BT' cables are compatible with 'standard' ones (if indeed
there is such a standard), I decided it didn't matter since I can probably
make 10 home-made ones for the price of a commercial pre-assembled one (plus I
seem to have a lot of spare phone extensions lying around).

Stop Press! - I have just done some more googling now and this is what I've
found:
A BT socket is known as LJU.
Google for "RJ45 to LJU adapter" to bring up loads of places you can buy them.
However you are right, it seems they only sell the extension ends (RJ45 PLUG
to LJU SOCKET) and not the other way around.

Using Yahoo! I finally found this site which shows a wiring diagram for LJU to
RJ45. Bingo!
http://www.mediahub.co.uk/support/rj...ng/wiring.html

It has a resistor and an capacitor in the circuit. I'm not an electrician so I
don't know why they are there, however, I'm pretty sure you don't need them
(as all we are really doing is extending the phone cable with a bit of Cat5
cable in the middle). Hopefully, there's an electrician out there who can
explain in more detail...

So, if you wire your RJ45-LJU cables according to the diagram above they
should in theory be compatible with the pre-assembled adapters you can buy.
Although this remains to be tested, so if you try it let me know what happens.

HTH,

PSB

Note - If you have Home Highway or another ISDN product you can use a standard
ethernet patch cable to patch your ISDN modem through the CAT5 network.

Note for Newbies - Be careful not to patch your phone newtork into your data
network (i.e. don't patch your phone line into an ethernet hub/switch) it
won't work!

--
To measure an animal's hairiness, simply divide its width when wet over its
width when scared.

In message <c084a8$92l$(E-Mail Removed)>, PsychicStickleBrick
<(E-Mail Removed)> writes

>To make a pair of patch cables, I would take one standard phone extention
>cable, cut it in two (to desired proportions), and fix an RJ45 onto each of
>the severed ends making sure to wire the pins the same on both. One bit goes
>from the BT phone socket to the patch panel, and the other bit is a phone
>extension lead which plugs into an RJ45 socket. This setup seems to work with
>no problems.

If you don't want to make your own cables you can buy ready-made cables.
It's worth noting that you can connect from the BT socket to RJ45 using
an ordinary modem cable. Although the plug is smaller than RJ45 it fits
the socket, connecting with the centre 6 pins of the RJ45 socket. I
found that I could buy RJ45 to phone adapters but not vice-versa,
probably because there is very little market for them.

[...]

>So, if you wire your RJ45-LJU cables according to the diagram above they
>should in theory be compatible with the pre-assembled adapters you can buy.
>Although this remains to be tested, so if you try it let me know what happens.

There are two different types, depending on whether you are connecting
to a master socket or not.



--
Bernard Peek
London, UK. DBA, Manager, Trainer & Author. Will work for money.

"PsychicStickleBrick" <(E-Mail Removed)> wrote in
news:c084a8$92l$(E-Mail Removed):

>
> "anthony james" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed) om...
>> What's the accepted way of using your CAT5 network as telephone
>> extensions?
>>
>> Last time i bodged it with two phone extention leads and replaced the
>> plug on one with an RJ45 and the socket on the other. This time
>> round i was thinking of getting BT to move the incoming line to
>> node0.
>>
>> I see you can buy 'RJ45 to BT' adaptors but this in only at the
>> extension end and i'd need to get the BT wires onto the right CAT5
>> wires. Is there a guide anywhere?
>
> Anthony,
>
> I have a similar setup: Each room in our house has two cat5/RJ45
> sockets which run back to a patchpanel / Node0 in the study. The BT
> phoneline enters the house at Node0 and lines are patched-in as
> required (The network is mainly used for ethernet and there is a
> 16-port ethernet switch also patched in to most rooms).
>
> To make a pair of patch cables, I would take one standard phone
> extention cable, cut it in two (to desired proportions), and fix an
> RJ45 onto each of the severed ends making sure to wire the pins the
> same on both. One bit goes from the BT phone socket to the patch
> panel, and the other bit is a phone extension lead which plugs into an
> RJ45 socket. This setup seems to work with no problems.
>
> When I investigated this about a year ago, I couldn't find any wiring
> standards on the internet for how the four (or six) wires of the phone
> cable match up to the 8 pins of the RJ45. To buy a proper adapter was
> expensive, so I didn't bother and just guessed. Although it would be
> nice to know if my bodged 'RJ45 to BT' cables are compatible with
> 'standard' ones (if indeed there is such a standard), I decided it
> didn't matter since I can probably make 10 home-made ones for the
> price of a commercial pre-assembled one (plus I seem to have a lot of
> spare phone extensions lying around).
>
> Stop Press! - I have just done some more googling now and this is what
> I've found:
> A BT socket is known as LJU.
> Google for "RJ45 to LJU adapter" to bring up loads of places you can
> buy them. However you are right, it seems they only sell the extension
> ends (RJ45 PLUG to LJU SOCKET) and not the other way around.
>
> Using Yahoo! I finally found this site which shows a wiring diagram
> for LJU to RJ45. Bingo!
> http://www.mediahub.co.uk/support/rj...ng/wiring.html
>
> It has a resistor and an capacitor in the circuit. I'm not an
> electrician so I don't know why they are there, however, I'm pretty
> sure you don't need them (as all we are really doing is extending the
> phone cable with a bit of Cat5 cable in the middle). Hopefully,
> there's an electrician out there who can explain in more detail...
>
> So, if you wire your RJ45-LJU cables according to the diagram above
> they should in theory be compatible with the pre-assembled adapters
> you can buy. Although this remains to be tested, so if you try it let
> me know what happens.
>
> HTH,
>
> PSB
>
> Note - If you have Home Highway or another ISDN product you can use a
> standard ethernet patch cable to patch your ISDN modem through the
> CAT5 network.
>
> Note for Newbies - Be careful not to patch your phone newtork into
> your data network (i.e. don't patch your phone line into an ethernet
> hub/switch) it won't work!
>
> --
> To measure an animal's hairiness, simply divide its width when wet
> over its width when scared.
>
>
>

When I was putting in LAN cabling at home, I looked up the colour codes
on the 'net. I also had a Maplin catalogue so was able to check in
there, when ordering the cable. Guess what? It was different to that on
the 'net!

Also from Maplin's catalogue, I ordered the tool for press-fitting the
cable to the network sockets. On the packaging was the colour-coding
that '...should be used...'. Guess what? Different again! I ended up
just making sure it was the same at both ends.

If there IS a standard, and I guess there probably is, where is it
published and can it be relied upon to be the same as is actually used
in the field?

Alan S.

"Alan S." <(E-Mail Removed)> wrote in message
news:Xns948AB80F15B95usenetnojunkaspal@195.129.110 .68...
> "PsychicStickleBrick" <(E-Mail Removed)> wrote in
> news:c084a8$92l$(E-Mail Removed):
>
> >
> > "anthony james" <(E-Mail Removed)> wrote in message
> > news:(E-Mail Removed) om...
> >> What's the accepted way of using your CAT5 network as telephone
> >> extensions?
> >>
> >> Last time i bodged it with two phone extention leads and replaced the
> >> plug on one with an RJ45 and the socket on the other. This time
> >> round i was thinking of getting BT to move the incoming line to
> >> node0.
> >>
> >> I see you can buy 'RJ45 to BT' adaptors but this in only at the
> >> extension end and i'd need to get the BT wires onto the right CAT5
> >> wires. Is there a guide anywhere?
> >
> > Anthony,
> >
> > I have a similar setup: Each room in our house has two cat5/RJ45
> > sockets which run back to a patchpanel / Node0 in the study. The BT
> > phoneline enters the house at Node0 and lines are patched-in as
> > required (The network is mainly used for ethernet and there is a
> > 16-port ethernet switch also patched in to most rooms).
> >
> > To make a pair of patch cables, I would take one standard phone
> > extention cable, cut it in two (to desired proportions), and fix an
> > RJ45 onto each of the severed ends making sure to wire the pins the
> > same on both. One bit goes from the BT phone socket to the patch
> > panel, and the other bit is a phone extension lead which plugs into an
> > RJ45 socket. This setup seems to work with no problems.
> >
> > When I investigated this about a year ago, I couldn't find any wiring
> > standards on the internet for how the four (or six) wires of the phone
> > cable match up to the 8 pins of the RJ45. To buy a proper adapter was
> > expensive, so I didn't bother and just guessed. Although it would be
> > nice to know if my bodged 'RJ45 to BT' cables are compatible with
> > 'standard' ones (if indeed there is such a standard), I decided it
> > didn't matter since I can probably make 10 home-made ones for the
> > price of a commercial pre-assembled one (plus I seem to have a lot of
> > spare phone extensions lying around).
> >
> > Stop Press! - I have just done some more googling now and this is what
> > I've found:
> > A BT socket is known as LJU.
> > Google for "RJ45 to LJU adapter" to bring up loads of places you can
> > buy them. However you are right, it seems they only sell the extension
> > ends (RJ45 PLUG to LJU SOCKET) and not the other way around.
> >
> > Using Yahoo! I finally found this site which shows a wiring diagram
> > for LJU to RJ45. Bingo!
> > http://www.mediahub.co.uk/support/rj...ng/wiring.html
> >
> > It has a resistor and an capacitor in the circuit. I'm not an
> > electrician so I don't know why they are there, however, I'm pretty
> > sure you don't need them (as all we are really doing is extending the
> > phone cable with a bit of Cat5 cable in the middle). Hopefully,
> > there's an electrician out there who can explain in more detail...
> >
> > So, if you wire your RJ45-LJU cables according to the diagram above
> > they should in theory be compatible with the pre-assembled adapters
> > you can buy. Although this remains to be tested, so if you try it let
> > me know what happens.
> >
> > HTH,
> >
> > PSB
> >
> > Note - If you have Home Highway or another ISDN product you can use a
> > standard ethernet patch cable to patch your ISDN modem through the
> > CAT5 network.
> >
> > Note for Newbies - Be careful not to patch your phone newtork into
> > your data network (i.e. don't patch your phone line into an ethernet
> > hub/switch) it won't work!
> >
> > --
> > To measure an animal's hairiness, simply divide its width when wet
> > over its width when scared.
> >
> >
> >
>
> When I was putting in LAN cabling at home, I looked up the colour codes
> on the 'net. I also had a Maplin catalogue so was able to check in
> there, when ordering the cable. Guess what? It was different to that on
> the 'net!
>
> Also from Maplin's catalogue, I ordered the tool for press-fitting the
> cable to the network sockets. On the packaging was the colour-coding
> that '...should be used...'. Guess what? Different again! I ended up
> just making sure it was the same at both ends.
>
> If there IS a standard, and I guess there probably is, where is it
> published and can it be relied upon to be the same as is actually used
> in the field?
>
> Alan S.

The colours don't matter, just so long as the wires connect the right pins.
(e.g. 1 to 6, 2 to 4 etc.)

>The colours don't matter, just so long as the wires connect the right pins.
>(e.g. 1 to 6, 2 to 4 etc.)
>
Surely you mean 1-1, 2-2 etc..
There are different standards for data cabling, the one currently in
use in the UK is TIA-EIA 568 B. There is a standard for telecoms
cabling on cat5 to prevent interconnection between data and telecoms
eqpt and subsequent blowing up of either appliance!
And it does matter which colours are used for which pins as the
twisted pairs are 'balanced'.
Off the top of my head the colours are.

Solid Trace
1- white orange
2 - orange white
3 - white green
4 - blue white
5 - white blue
6 - green white
7 - white brown
8 - brown white

If I'm connecting 1 BT line to a cat 5 cabling system I use a standard
secondary, (without Capacitor etc..), Line Jack Adaptor, (or LJA) with
a standard, (or identical type to what you're putting on the end eg
phone or modem), phone lead into the BT socket.
...

SJW
A.C.S. Ltd.

"PsychicStickleBrick" <(E-Mail Removed)> wrote in message news:<c084a8$92l$(E-Mail Removed)>...
> "anthony james" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed) om...
> > What's the accepted way of using your CAT5 network as telephone
> > extensions?

> http://www.mediahub.co.uk/support/rj...ng/wiring.html
Good site.

>
> It has a resistor and an capacitor in the circuit. I'm not an electrician so I
> don't know why they are there, however, I'm pretty sure you don't need them
> (as all we are really doing is extending the phone cable with a bit of Cat5
> cable in the middle). Hopefully, there's an electrician out there who can
> explain in more detail...

You do need them. All BT phones are a 3-wire conection.

BT use a "master socket" to separate the ringing current for the bell
from the speech circuit. The capacitor goes from the 'a' wire to the
top of the bell, and the other side of the bell goes to the 'b' wire.
So the capacitor "creates" a 3rd wire that is parallelled to all the
phones to power the bell.

The resistor is just there to provide a path to the capacitor if no
handsets are connected. This allows the automatic tester in the
exchange to tell the difference between a broken pair to a subscriber,
and subscriber who has jacked out all the phones. It's not very
important.

You only need the cap/res circuit at the master. In a structured
wiring context you get a "master" adaptor and optional "slave" ones
(you can make a slave my opening a master and snipping off the cap &
res). Then you can parallel up circuits on the patch panel, fit a
master to any one of the remote sockets and slaves to the others, and
ring multiple phones with one number.


If you buy US-standard phones, then they plug straight into an RJ45
and don't need adaptors. Thier bell wiring is all internal.

On Mon, 09 Feb 2004 16:31:37 +0000, Bernard Peek wrote:

> I found that
> I could buy RJ45 to phone adapters but not vice-versa, probably because
> there is very little market for them.

Assuming you mean an adapter with an RJ12 (UK phone) socket and RJ45 plug,
I have one here. It is marked "MOD-TAP LTD LINE ADAPTER 42-114".

It's for connecting my laptop to the phone system at work, where all the
structured cabling is RJ45/CAT5. It has the appearance of a low
production volume device (the label is typewritten and stuck on). It does
work

I know nothing more about this thing, or whether they still sell them. Or
even if they're still in business. It was provided sometime in the distant
past by our PC department.

Regards, Ian