Level 1: Cadet

multiple phones

I have a faxphone answering machine connected directly to the modem at a central point in the house.

NBN is connected.

I would like a cordless phone base station  on my desk in my office.

I would like to be able to use the wall phone in the kitchen.

I would like a cordless phone in the bedroom running from the base station in the office.

At the moment the fax phone is all that is connected but I have phone sockets everywhere in the house which I cant use since NBN was installed.There is a phone socket on the wall near the modem.

Can you tell me if the splitter I used to use with ADSL can be used to run my other phones.??

If so how do I connect it??

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Level 22: Superhuman
Level 22: Superhuman

Re: multiple phones

That is a fairly complex question - the number of handsets is part of it, the presence of a Telephone /fax is the major issue.. 


Do you know if any work was done at the time the NBN service was connected, to disconnect any of the existing wall outlets? What sort internet service do you have? Is there any other NBN device installed in addition to the Telstra modem?


1. It might be possible you use the existing telephone cabling and connections - but a bit more detail is required - especially about the wiring arrangement of the other wall outlets..  it could be possible to use a simple telephone (RJ 11/RJ12 type) splitter to connect the phone/fax to the modem phone port and also to the building cabling that exists provided those additional outlets are not connected to the NBN service if it is DSL. then connect handsets to the points where you want them. All devices would be on the same number and you would have to consider the number of rings before the fax answers - among other things..


2. If you have a Smart Modem 2, it has a DECT (Cordless) base built into it which will allow several handset to connect (all on the same number). There is also a phone port to which you might be able to connect the phone/fax in parallel with the cordless DECT handsets..  the Telstra range of handsets can be seen here..  and the best option would be to go with devices that are identified as Smart Modem compatible..


3, If you already have a cordless base and handsets, you might be able to connect that and the phone/fax at the modem using the same splitter arrangement as option 1. above.


It might take a bit of trial and error to work out the best solution..


It also might be possible to get a second home phone line for the phone/fax..  best to be raised with Telstra and I would suggest you would be better to visit a Telstra store (not a franchise) rather than try to explain your needs to the Telstra Customer Support messaging 'Consultants' who have limited knowledge of the Telstra products and anything beyond a single service connection..

Stevo 52
Too many devices, probably an addict :-) also a tinkerer and developer of stuff..
Not with Telstra, just another customer like you!
Level 25: The Singularity
Level 25: The Singularity

Re: multiple phones

As long as the REN of all the devices in total is 3 or less (fax/phone may be more than 1.0), then it should be possible.


The ADSL splitter won't work for this purpose.


The alteration to the wiring will depend on what type of NBN connection you have.


If you have FTTN/C (ie the modem connects in the same manner as your old ADSL connection), then you will need to get a new socket installed and have that connected to the other sockets in the house. The modem would then plug into that socket.


If you have FTTP, HFC, or FW, then you would just need to get the incoming line disconnected from the primary socket and then the modem's phone socket could plug straight into the phone socket to connect with the others.

Never be afraid to back yourself when trying new things, just always make sure you have 3 escape routes if things go wrong.
Level 1: Cadet

Re: multiple phones

Hi  SteveW,

1.None of the existing wall outlets were disconnected.

In fact the one in the bedroom is fairly new and was made NBN ready about 12 months before.

2.The internet service is NBN...using DOT [digital office technology}

3.No other NBN device is installed except the modem.the TV runs on the wifi.

4.The  desktop Computer is in the office and runs form a cable on the wall somehow connected to the modem in the other room.

5.I dont have the fax phone set to receive faxes automatically.Husband  mostly uses it as a telephone and on the rare occasion I send a fax/receive a fax I do it manually by pressing the button on  the machine.

6.The other phone sockets in the walls all over the house  are not connected to the NBN.

7. I think your option one sounds like the best bet.However, I dont know what order to plug the leads in. There is a black lead running from the telfax machine into the back of the modem and that all works at the moment. there is a phone lead running from the wall socket  behind the modem and telfax which would plug into the splitter but do i plug it into the phone or ADSL port?The black lead from the telfax would go into the other port..then the main lead from the splitter looks just like a short phone cord.Does this go into the back of the modem?

Level 22: Superhuman
Level 22: Superhuman

Re: multiple phones

The best configuration for this needs a bit more detail to be sure of what would work, it is hard to do this sort of thing remotely, without being 'hand-ons'. There are constraints on how many devices can be connected on the single 'Phone' connection of the modem (the REN that @Jupiter mentioned). 

Can you help by providing:

A. Photos of:

  1. Back of the modem showing all connections
  2. Wall connection for Internet cable
  3. Phone/fax device showing the connections
  4. The wall telephone connections (with and without cables/phones)
  5. Existing Wall phone
  6. Other existing handsets including any cordless devices
  7. Any other devices such as PC's or associated wall outlet connections

B. A list of the phones you want connected and the make/model of each device.


As CrowdSupport is a public forum, be privacy/security conscious when taking the photos and if you prefer you can send photos by a private message.


What is going to be a big unknown is the cabling arrangement of the wall sockets etc. 


Option 1 is the simplest method but may not be technically possible.


Stevo 52
Too many devices, probably an addict :-) also a tinkerer and developer of stuff..
Not with Telstra, just another customer like you!

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