8870 DTMF Decoder interface with Nokia 1600 headphone pin

Dear All,

How to take a DTMF o/p through mobile headphone pin. There are two or three connections. One is left spk, 2nd is right spkr, where to connect to get DTMF o/p.
Plz help me, i m confused for this silly ques.
Mr.Bhargav --plz reply ASAP, u know this.
Ultimately . i m making land rover robo using cellphone, but not getting dtmf output from headphone pin or what will be d o/p. plz helppppppp.
Regards,
Nilesh

Dear All,

How to take a DTMF o/p through mobile headphone pin. There are two or three connections. One is left spk, 2nd is right spkr, where to connect to get DTMF o/p.
Plz help me, i m confused for this silly ques.
Mr.Bhargav --plz reply ASAP, u know this.
Ultimately . i m making land rover robo using cellphone, but not getting dtmf output from headphone pin or what will be d o/p. plz helppppppp.
Regards,
Nilesh

nils_ec

i have worked on this project and also have submited my work to this site
only u have to do is to use any one side of the headphones either Left or right any one
then simply connect it to the 8870 DTMF decoder
MAKE SURE THAT THE TOUCH TONE VOLUME IS FULL AND THE JACK IS CONNECTED TO PHONE INDICATING ON CELL THAT THE PHONE IS ENTERED IN A HEADSET MODE
use a simple mobile for the project like 1100 which is ideal cell for this type of projects

Dear Nilesh,
I am attaching the complete circuit diagram with 8870 DTMF and PIC microcontroller. I have also mentioned the jack pin with label. You can connect any nokia phones like 2100,3210,3330,3410,3510,5210,6600,7650,8210,8310,8850 and so on. Hope your problem will be solved easily.
Regards
Abdul

Thank you frnd... it works...

How cud we detect the dtmf from touch screen phones..its nt giving sufficient voltage thru headphone output..

How cud we detect the dtmf from touch screen phones..its nt giving sufficient voltage thru headphone output..

Robowaala

MAKE SURE THAT THE TOUCH TONE VOLUME IS FULL AND THE JACK IS CONNECTED TO PHONE INDICATING ON CELL THAT THE PHONE IS ENTERED IN A HEADSET MODE

Dear Nilesh,
I am attaching the complete circuit diagram with 8870 DTMF and PIC microcontroller. I have also mentioned the jack pin with label. You can connect any nokia phones like 2100,3210,3330,3410,3510,5210,6600,7650,8210,8310,8850 and so on. Hope your problem will be solved easily.
Regards
Abdul

rezferten

if we connect direct from headphone to ic mt8870,maybe the signal too tiny?i making te samme circuit in datasheet of mt8870 but it not working,plz hellpppppppppppp!

thedung, create a thread for yourself. Dont open old threads.

@ Thedung......
no amplifier is required..from cell to 8870 ........ic works fine on recived signal from cell.......only you should have touch tone volume full.....(based on my experience)
as....there is a inbuilt differential amp.......in it......