How To Connect All Your Home Phones To Your VoIP Service

Young Woman Using Cordless Phone
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Once you are satisfied with your VoIP service, you might want to make optimum use of your home telephone sets and phone wiring. You can do this as a means to terminate your PSTN service and switch completely to VoIP.



Time Required:

Some minutes

Here's How:

  1. Disconnect from the PSTN phone company.This is a security measure to ensure that your ATA does not burn due to power from the PSTN line. To do this, find the demarc and open it. There are two series of wires: one going into the building to your phones, and the other going outside to the provider’s network. Disconnect the one going to the outside. You are disconnected from the PSTN.
    1. Read the tips below.
  2. Check this by taking a up a phone. If you hear no dial tone, you are disconnected. You will however not be able to check this if you have had your connection terminated with your PSTN service provider before.
  3. Make sure your DSL VoIP service is working. Also make sure that the PSTN line is not reconnected again, as this will burn your ATA once it connects.
  4. You now have an isolated internal phone circuit. Connect your ATA to any modular jack in your phone circuit, using a RJ-11 jack. Take a phone to check for a tone. If there is, it works.
  5. Most ATA’s are designed to handle the power requirements of only one phone or two, so you should know well about your ATA’s specifications to know how many phones your circuit can contain. It is better to know the number of phones before buying the ATA, so that you can choose one with adequate powering ability.
  1. Refer to Figure 1 to get an illustrated idea to the connection.


  1. Actually, whether you have one phone set or more, they are linked together by modular jacks. A modular jack is a small box linking one or two phone wires. Your phone wiring closes at the point of entry of your telephone service, a grey or brown box fixed by your phone company into your house. This is called the demarc and is the point from where your home connection is linked to the service’s network.
  2. Note that this tip/hack will not work if your ADSL service uses your PSTN wire. There should be different cabling for it.

What You Need:

  • A good phone circuit. You already have your home PSTN wiring in place.
  • A broadband (normally ADSL) VoIP Service.
  • An Analog Telephone Adapter (ATA)