dtmf decoder 8870 not working

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Dalvir

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i used 8870 i connect the hand free to 8870 i press key it not generate any out put
i check crystal frequency it is 2.9MHz
so i replace the crystal
but problem still remain
then i replace both capacitor of 33pf & crystal
but problem sill remain i change ic 8870 with a ic 8870 which work in other circuit
but the problem still remain



i change the resistance b/w pin 2 &3 100k by 4.7k
 

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