Mt8870 dtmf decoder circuit

[atollp]

Hey forum...

I'm new. I'm working on a DTMF decoder circuit for a robot, but right now I'm working on getting tones from a cell phone decoded. This schematic is pretty clear on it. Wondering if anyone out there has tried this circuit or has tried one like it and your experience with it? Success? Failure?


http://technicksforu.blogspot.com/2008/08/mobile-controlled-robot.html

 

[OLIVE2222]

Hi atollp and welcome to this forum !

The 8870 is an industry standard component for tone decoding. It' a proven and easy to work with part.
Olivier

 

[atollp]

Thanks for the reply!

It looks like it will work. I'm excited to see. Have you worked with it personally?

 

[OLIVE2222]

yes I have worked with in the frame of a phone call locker.
Olivier

 

[atollp]

So it sorta works....tested it out and got off and on response...a little shaky. Not sure if it is the MT8870 or what. I figure it is, since the chips I have have been sitting without any protection (CMOS) in drawers for months. They should have been better protected. Assuming they are damaged. Waiting for new ones to get here then will test again. Otherwise I did get a good response, so I know the rest of the circuit is connected correctly.