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Wave Shield voltage change with audio levels
Moderators: adafruit_support_bill, adafruit

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Wave Shield voltage change with audio levels

by Raythe54 on Sun Sep 16, 2012 11:49 pm

Hello,

Sorry for the newbie question.

I'm trying to find out where best to get voltage changes with audio level on a Wave Shield to link into an Analog In. An Instructable I'm attempting to follow shows linking R7 to an input should do it, but I don't see the voltage fluctuate on my digital meter.

Any idea if this should work or if there's a better place to tap off of?

Thanks, in advance,
Ray
Raythe54
 
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Re: Wave Shield voltage change with audio levels

by adafruit_support_bill on Mon Sep 17, 2012 5:56 am

R7 is a good place to tap into the signal. But you won't be able to see much with your multimeter because the signal is changing too fast for the multimeter to measure.

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Re: Wave Shield voltage change with audio levels

by adafruit_support_rick on Mon Sep 17, 2012 6:04 am

input voltages will be very low. If you just want to feed it into an ADC, you'd be better off sampling the output voltages going to the speaker.
Have a look around C9. For input to the ADC, use a diode to get only the positive voltages (music signals will be pretty much symmetrical, so you can simply sample half the waveform and extrapolate).

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Re: Wave Shield voltage change with audio levels

by Raythe54 on Mon Sep 17, 2012 11:24 am

I'll look into that - thanks a million for the reply!
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Please be positive and constructive with your questions and comments.