I just came from a new client who told me Comcast had verified their line was good to the interface so it was their problem.

Truth is that they have a 308 doorphone so I explained that it is a system device and nothing to do with Comcast. They have no display sets and my book was home so I'm returning next week to see if the software went flat although I thought default was all doorphones ringing all stations?..

I checked the IW as good and suspect the adapter at the KSU has failed

another clue.
Neither doorphone has any talk battery but on only 1 pressing the call button delivers DT?

Does anyone have a way for me to determine if it is the adapter without buying one to swap?

Thanks

I guess there aren't many of these out there anymore?

Try momentarily shorting the pair that goes to the door box. If the adapter is good, this should start the ringing cycle at all programmed stations. Even if there's nothing programmed to receive ringing for some odd reason, you should hear some relay clicking. If you don't, then yes, the adapter is probably bad. Although this system has been discontinued, I can't imagine that you can't get a replacement from a refurbisher if needed. It sucks that you don't have a display phone. Have you checked to see if the system might be in the night mode where nothing is programmed to receive door box ringing?

Thanks ED,

It was simpler. They had downgraded a few years ago & had only SLT's and cordless phones left. 2nd visit I brought a system phone to check programming. I discovered although the analog component was working. there wasn't any battery at all on the data pairs of any port. Wish I would have checked that before I bought the Doorphone adapter though.

Thank you for the response.

Ralph