testing voltage on phone line

Old 03-06-04, 05:35 PM
HairyKnuckle's Avatar
Thread Starter
Join Date: Mar 2004
Posts: 71
Upvotes: 0
Received 0 Upvotes on 0 Posts
testing voltage on phone line

I am considering changing my land based phone line over to the internet service. (Vonage like company) I want the ATA device to connect to my home wiring however, so I can use the three extensions already in the house.

I have looked in my phone box out on the side of my house and I have two 4 strand phone lines coming into/out of the customer side. One 4 strand wire goes into the ground along side the foundation with a bigger thicker cable and the other 4 strand wire comes into my house. I have two lines in my house and I only want to disconnect one of them as one is personal and one is for work. The box on the side of the house has two blues wires from this four strand cable hooked up to a jack, and the other two wires (I think they were orange) hooked up to another jack. Then there is another 2 blue wires coming form the ground hooked to a third jack. This is all on the customer side of my phone box outside. If I disconnect the first set of blue wires, which I think is the circuit I want my phone internet connection to go on, will that disable PSTN voltage in my house for the two blue wires?

Also, to test voltage in the phone line, how do you use the Multimeter, what setting do you put it on?
Old 03-24-04, 07:21 PM
Join Date: Dec 2003
Posts: 30
Upvotes: 0
Received 0 Upvotes on 0 Posts
well all i can make of the post is you need to put your multi meter on dc voltage to test telephone voltage 96 volts ringing current
Old 05-12-04, 06:59 AM
Visiting Guest
Posts: n/a
Did you find a solution for this?

I am about to do the same with Vonage.
I got the equipment and installed on a single line although I would need
to have the device plugged into the walljack through the RJ11 wired in the house so my other phones can use this service.

Let me know if you find a solution.

Old 08-22-04, 08:30 AM
Visiting Guest
Posts: n/a
Smile connecting Voip to house phone wiring

There is some great information here. I just connected my Vonage to my home phone wiring and all phones now work perfectly!! One warning - if you have a monitored house alarm Your wiring might be slightly different because the alarm is often wired to interrupt (disconnect) all phones from the line when it calls the monitoring station.


I've cut and paste the primary info here to same some time
To answer your question I will first refer you to this excerpt from Vonage's FAQ:


"Can I use multiple phones with the phone adapter?

There are four ways to plug multiple extensions into your ATA. Please
note that currently only phone port 1 is used by our service.

You can purchase a multiple jack extension connector, and then connect
it to phone port 1 of the ATA. This will allow you to have multiple
phones on a single Vonage DigitalVoice line.

Some of our customers use cordless phone systems that come with a base
unit and extra handsets. The base station of the cordless telephone
plugs directly into the ATA. Multiple handsets can be placed anywhere
in the house.

You can purchase wireless phone jacks. The base unit connects to the
ATA and the wireless jacks plug into your household electrical
outlets. A telephone connects to the wireless jack. Please note that
only the phone attached to the base unit will display caller id
information. Also, during testing in our lab, we noticed sporadic
dropped calls on the extension phones and an inability to talk on more
than one phone at a time.

Some Vonage DigitalVoice customers have plugged the ATA directly into
the existing telephone wiring in their homes.

The manufacturer (Cisco) of the adapter does not recommend hooking
anything to the adaptor other than a telephone, but you can seek
advice from an electrician or someone who is familiar with internal
telephone wiring on how to best connect it to your current wiring to
take advantage of multiple extensions. We would advice that you
pre-check the wiring on the jacks to make sure you don't have live
PSTN voltage on the jacks before connecting them to the ATA (this can
be easily done by using a line tester such as those that are available
at Radio Shack). Be advised that any damage resulting from practices
contrary to manufacturers recommendations for the ATA will not be
covered by warranty.


(Vonage has recently switched to a Motorola supplied ATA, but the
information is still valid)

Now, please note that unless you are very familiar with residential
telephone wiring techniques, you may wish to get a telecom specialist
to help you with the last option. In this option, it is necessary to
check, double-check, and triple-check that your in-home wiring is
completely separated from the telephone company's wiring that leads to
the junction box/demarcation point for your home, before attempting to
connect the ATA to your home's wiring. Failure to confirm that the
wiring is disconnected *WILL* destroy your ATA.

I should also take this opportunity to remind you to review the Google
Answers disclaimer, and that ultimately you should seek the advice of
a local electrician or telecom specialist before performing any of the
steps below, since neither myself nor Google Answers are liable should
you damage your equipment.

The steps that the electrician or telecom specialist would need to
take (or you, if you feel that you are familiar enough with telephone
wiring techniques) are:

- unplug all telephones and other devices from all telephone jacks in the home
- open up the junction box (often located outside your home)
- disconnect each of the telephone company's lines from the
terminating blocks, wrapping each wire end with electrical tape for
- ensure that all of the wires for each extension line leading into
the home are secured to the terminating blocks
- use indelible ink on a sheet of PVC sheet to write: "DO NOT
and attach the sheet securely inside the box in case a telco
technician comes by unannounced one day
- use a multimeter to check for voltage across any of the four
terminals for the in-home wiring (there shouldn't be anything greater
than 1 VDC. If there is, something else is already pumping power into
your in-home wiring)
- close the junction box, and secure it with wire or cable ties
- back in the home, use a standard telephone patch cable to connect a
telephone to an extension wall jack
- using another standard telephone patch cable, connect the ATA to
another telephone wall jack
- pick up the telephone handset that you plugged into the extension,
listen for a ringtone
- if you hear a ringtone, you may proceed to plug your other phones
back into their respective wall jacks

NOTE: The ATA's telephone jack output power was only designed for one
phone. Using multiple handsets simultaneously (ie. several people
picking up handsets for the same call) may degrade the audio signal;
if this happens, hang up some of the extensions.

I hope this helps,

Google Answers Researcher

Thread Tools
Search this Thread
Ask a Question
Question Title: