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multiple phone hookup question.

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New Poster

multiple phone hookup question.

How do I hook up multiple phones to a new digital voice installation?

Can i just plug into my old phone system input bus?

Expert

Re: multiple phone hookup

There can be several ways to connect the eMTA to the inside phone wiring.

 

First step is to make sure the old telephone service is disconnected.  This is normally at the NID, network interface device, the gray box on the side of the house.  Unplug the small phone cord from the jack in the NID, and mark it so it will not be connected back by accident.

 

Once the inside phone wiring is disconnected from the old incoming ILEC service, it is safe to hook the eMTA to the inside phone wiring.  Usually the eMTA is installed in a room that has a existing phone jack connected to the inside phone wiring in the home. Take a standard phone cord, plug it in the phone jack in the room and the other end goes to the L1/L2 jack on the eMTA telephony modem.  That feeds the jacks in the home to the talk battery voltage on the eMTA and supplies your dial tone and ringing voltage to all phones connected in the home.

 

Special wiring needs to be done when there is a alarm panel in the home, normally the Comcast installer does this.  If the room that the eMTA doesn't have a phone jack, then a inside wire needs to be installed to connect the eMTA to a different point where there is access to the inside phone wiring in the home.

New Poster

Re: multiple phone hookup

That's great.  Just what I was thinking.  The comcast instructions "imply" a single phone.  I also wasn't  sure if the eMTA would be able to power 3 or 4 base units; but I guess they all have their own power anyway.

Thank's for the straight info.

jg

Expert

Re: multiple phone hookup

A typical eMTA is spec'd at 5 REN per line, so it's enough to power 5 old fashoned phones with real ringers. 

 

On all the new electronic phones the REN is a fraction of old mechanical ringers.  If each phone has a REN of .25, then you can power 20 phones.  .25 x 5 = 20  If each phone the REN is .5 then you can power 10 phones.

New Poster

Re: multiple phone hookup

Assuming all of the above... are there restrictions using more than one handset... does Comcast discreet filter the lines?  I've tried disconnecting outside service but once I plug in a second handset (in a different room) neither handsets work and the base says "handset in use".

 

Thoughts?

Expert

Re: multiple phone hookup


invaderzim wrote:

Assuming all of the above... are there restrictions using more than one handset... does Comcast discreet filter the lines?  I've tried disconnecting outside service but once I plug in a second handset (in a different room) neither handsets work and the base says "handset in use".

 

Thoughts?


You have an internal wiring problem....  Your best bet is to contract a low voltage company and have them trace out the issue(s) and affect repair...

 

-=Ray=-