atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems real interesting service call

"5. Yes, I could dial out on a rotary phone or phone without polarity issues."
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If I read this correctly OP says rotary AND DTMF with inherent polarity guard work correctly. That would indicate that the C.O. still has DTMF receivers assigned.

Thanks for your additional comments but here is some more clarification:
1. The CO side of the NID was tested and was the correct polarity and I could dial out.
2. During this episode, one jack with reversed wiring did show correct polarity and I could dial out.
3. Yes, if the wires were reversed twice they would be back to original but remember, they were switched once in the basement.

Put the handset to your ear and punch a few numbers on the pad. If you here the dtmf tones your line is straight. If you get dead air its reversed.

loop start
T - GRND
R - -48vdc

John, that's what I did initially to discover that I had a problem and on all the jacks. The problem is fixed now.
Arthur, I was the one who made him switch the wires twice at the NID because I thought he made a mistake the first time. I watched him do it a second time and still got reversed polarity. Here is a summary:
1. All jacks showing reversed polarity. Must be a Ma Bell problem.
2. Installer switches wires at NID for 1st time. All jacks still showing reversed polarity, CO line correct polarity.
3. I think installer must have accidentally not switched them, so I ordered him to switch them again while I watched him do it. All jacks still showing reversed polarity.
4. Wires switched in basement. All jacks OK.
Bottom line: this seems impossible and why I posted this to the forum.

You said you have two lines. Are you sure he reversed the correct line at the NID?

Yes, I thought of that as well. I can verify which is line 1 and line 2 as I have speed dial on line 1 but not line 2.

There are easier ways to ID telephone lines.

ANA and CID are two of them.

OK, I'll bite. What do ANA and CID stand for?

What does phonenut stand for?

I think Arthur was referring to ANI (automatic number identification) and CID (caller id). They two are not related nor compatible with each other. ANI is only available to WATS (wide area telephone service) subscribers such as toll-free services. ANI identifies the billing number of the calling party. ANI is not blocked by feature codes, and (someone correct me if I'm wrong), it can't be spoofed easily like CID can.