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Caller IDs Indian and US systems

I bought a land line phone with caller ID in the US and tried to have it work in Kolkata (India). The caller ID function does not work. It turns out that the US and India use different methods to transmit the caller id information [1] and you need a converter [2] to get the US phone to work on the Indian system.

[1] In the Netherlands, Saudi Arabia and India, the caller ID standard is DTMF. In the US it is the Bellcore FSK standard and in Germany it is the ETSI FSK standard.
The US also transmits both the user name and the phone number whereas the Indian system transmits just the phone number [artech].

[2] A DTMF to FSK converter is needed. Artech manufactures these calling them Caller ID Converter, DTMF to FSK. The model number is EX230.
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