well i build an home security for my finel project on elec.
i build it that whan ther is alart on some place it calling to some number that kept in the memory, and tell him what happen on the house.
i got problems on connectin the calling system, this is my problems
1) what is the recommended DTMF dialer for this project and most easy to use?
2) how i connect the DTMF dialer to the RJ9? ( we got only 2 cabels in our contry not 4, so only mic and sound i guess )
3) are all the contres got telephone standard or all contry got her own standard?
and what pass on the phone line? are this some kind of modulation?
4) how can i know when some one answer the phone?
5) how i connect the voice chipe to the RJ9 ? how voice move on the phone line?
tnx for all answers, sorry if i got bad eng ( not my lang
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