I need to design a simple call asnwering machine. i need to record the voice conversation from a telephone...and i am currently using APR9600 voice recording IC. But i am having some problems regarding how to interface with the telephone set when nobody is at home...
Plzz help!!
"how to interface with the telephone set when nobody is at home..."
Is there a difference in how to interface with the telephone set when nobody is at home, or when one or more people is at home?
Do you wonder about interfacing with a phone line, or how to control if the chip should record or if the call should be handled by the people who are at home?
i am having some problems regarding how to interface with the telephone set when nobody is at home... I think (s)he means "when the phone is not answered"
Erik
So what problems, exactly, are you having?
Don't you think it would be necessary to explain the problems before anyone will be able to help you resolve those problems...?
Connecting to Telephone Lines really is a specialist area, requiring specialist analogue design techniques. High voltages are present - not likely to be fatal, but certainly sufficient to give you a shock and to damage incorrectly designed and/or implemented circuits.
There are also legal restrictions about connecting to the Public Telephone Network. Remember that your telephone line connects direct from your location to the exchange - so, if you cause any trouble, they do know where you live...!
Unless you are experienced in this area, or working directly under the supervision of someone experienced in this area, you really shouldn't be messing with it. Instead, there are plenty of ready-made modules available to provide the line interface...
High voltages are present - not likely to be fatal, but certainly sufficient to give you a shock If you ever have been rewiring your phone lines when somebody called, you will know.
Unless you are experienced in this area, or working directly under the supervision of someone experienced in this area, you really shouldn't be messing with it. I happen to recall seeing an appnote for some phone stuff and this is DEFINITELY a matter of more than "connecting the wires"