home automation using telephone

[t_sanoop]

hi,
i want to do a home automation project using telephone.after a predefined number of rings, the controlling circuitry should be activated automaticall and after that if i press any phone key it should control the corresponding home aplliance.
is there any particular ic which will help to count the number telephone rings. i also want the details about dtmf reciever and transmitter ic.i request your help. pls help me by providing the necessary details.

thanking you,
sanoop

 

[akg]

i have done a proj like this. but it uses a pc. anyway adding a micro: to ur IC list will simplify the things . u will not need an ic to count the rings , search for telephone ring detector circuit in google. for other ics eg:- MM8870->dtmf detection , HT9200->dtmf generation lookup datasheets at https://www.alldatasheet.com

 

[Paul Obrien]

There have been, or at least it seems like it, dozen of these projects show up in electronics mags over the years.
**broken link removed**

 

[catcat]

When you press a button on the telephone, it emits a tone. you could make a curcuit to detect the various tones.

 

[zkt_PiratesDen]

actually 2 tones simultanously, hence dtmf (dual tone multi-frequency)
there used to be a tone decoder chip, lm567, i think. lotsa rc timing parts involved
be a good job for a PIC
look around, i`m sure its been done

 

[mramos1]

akg gave you the info you need to get started. ring detector (to count the rings), (and off-hook circuit; google for that), DTMF decoder (to see what key is pressed, etc. Not sure if you will need the DTMF generator. And a micro controller to signal or control things.

Also, beware the phone ring voltage in the US is like 90VAC 20Hz RMS.. That can break things is not wired correctly the first time

 

[catcat]

I read someere that it's 2 tones. Ifound some info on it:
https://electronics.howstuffworks.com/telephone7.htm

 

[AllVol]

This link might be of some benefit:
www.electronicsforu.com/electronics...uit/Oct-cir/cir1.htm&title=Teleremote Control