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What type of tone is available at pin 7? (DTMF)

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mytech

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Actually i wanted to know what type of tone would be available at pin 7. after constructed the circuit i gave tone o/p to input to the amp. but when i press the key it doesn't make any sense.. will it make sound if the circuit works?.. or let me know some ideas.. thanks..
 

Re: DTMF

Hi,
Yes , it should give a DTMF tone sound, the familiar sound that you hear when you dial from your tone output telephone. You may need to connect two low value ceramic capacitors ( 10 to 20 pf)from each point of the crystal to ground. Also the tone output is open source, so you can connect a 4.7K resistor from pin 7 to ground and connect pin7 and ground to your amplispeaker.
Regards,
Laktronics
 

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    mytech

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