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Landline caller ID


New Member
Does anyone know if the frequency shift keyed caller ID signal is standard on all calls, or is there an added fee to the phone company to provide it?


Well-Known Member
Most Helpful Member
in the USA it is standard. there was a time when you had to pay for it. there are actually two data blocks, the first one is caller ID for use by customer equipment, which can be turned off by the caller using *69 the other block can't be turned off, and is the one used by the 911 system


Well-Known Member
There is a list of phone key tones. There are 4 extra keys that are not on your phone and your not suppose to know about them, the operator is the only one that has them. You can buy ICs for making phone tones. Years ago I use to have this circuit it works great. Assume you want to make a free long distance phone call from point A to point B. Lets say you want to call California from NY. You call the long distance operator soon as she answers you push the P tone key this disconnects you from the operator she thinks that you hung up but your still connected to the long distance trunk line so now your connected to California as if your in CA on a home phone, now you can make local phone calls in CA for free. Call Germany long distance operator push the P button then you can make free phone calls to Germany. Assume you want to tap a phone call someones home phone push the I button it stops the phone from ringing now your connected to their phone if they make a call or receive a call you get to listen to both sides of the conversation. Phones have changed this is old technology that is probably worthless now. Tones from the speaker goes into the telephone mic. There is still secret stuff cell phone companies do not want you to know. Here are the key tones.



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Well-Known Member
Most Helpful Member
in the USA it is standard. there was a time when you had to pay for it.
I'm in the US with a landline. No CALLER ID unless you pay. We have no caller ID. We do have 4 cordless phones that would support it.
It's usually provided with VoIP phones.


There is Caller ID and ANI (Automatic Number Identification). You cannot block ANI. It's primarily used for billing. If you had an (800 or 900) number, you get ANI. Some large corporations might have ANI and not Caller ID.

Way back when, telephone signalling was in-bound. 2600 Hz disconnected billing.

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