Princess transformer on Comcast digital voice modem

[pa_bell1960]

 Hello Everyone. My name is Jim and I am of course new to your forum and glad to be here. I`ve been reading a lot of good stuff on here, and have plenty to ask later, but right now my concern is using a Princess transformer for my phone and will it damage the modem in any way? All my rotary phones work really well on this eMTA modem, so if anyone can help I would greatly appreciate it.   Jim

[Phonesrfun]

It should not be a problem, but lets explore some more.... 

1.  Does your princess have a hard-wired cord on it with spade ends, or does it have a modular plug?
2.  How are you connecting the transformer to the cord on the Princess?
3.  Looking at the modular phone jack on the back of the modem, hopefully there are only two little contacts, rather than four.  (You would need to unplug the phone plug from that jack to look inside the jack)

[pa_bell1960]

Hello Bill,  The Princess is modular, and is plugged into a jack here in my kitchen. Comcast wired the modem to where all the jacks in my house could still be used. The transformer I have has all modular wiring. Now I have a hardwired Trimline I intend to put a transformer on as well since it has the incandescent bulb. If this will work for the Princess should it not work for the Trimline as well?   Jim

[Phonesrfun]

You can try it and see.  Newer Trimlines used an LED and line current to light the lamp.

Some modems are set up with TEL1 and TEL2, but they usually come out in two separate jacks rather than coming out of one Jack. 

Without going into a lot of wiring dialogue, just try it and see.  If you hear some humming or experience some outage, then undo the transformer.  At 8volts, you are likely not going to do any damage in the short term, so all I can say is give it a try.

If it doesn't work, then lets go from ther

[jsowers]

Bill, you can check the cable that hooks up your modem to your phone wiring. If it just has two conductors, then you won't be connected to it on yellow and black (where a transformer would connect). Just red and green. You can tell the number of conductors by the brass "teeth" in the modular plug. If your modem hooks to the line with a four-conductor modular cable, look around for a two-conductor one and replace it. Sometimes those can be found at thrift stores. Sometimes they're cheapo cables, so be sure it works.

I've had a Princess transformer hooked to my POTS phone wiring for 20 years with no problems. I do make sure that my laptop modem and any electronic phone connects with a 2-conductor modular cable, just in case.

If your Princess or Trimline will be installed at one particular jack, you can also just take loose the yellow and black station wires at the jack and tape them up separately. Then wire the transformer to yellow and black at your jack faceplate for that phone only.

[pa_bell1960]

Well I have the transformer plugged in and I did the jack modification as suggested and everything is working fine. No problems with the modem. I want to thank everyone who responded to this post. Hope you don`t mind but I have a few more questions coming.   Jim