Parallax Scope and 500mv question

Redd Dawg

So I'm running just fine on an RC circuit with a piezo speaker, 1 uF Cap and 220 resistor. Looks great on the scope both in version 4 and version 5 of the os for the scope. Go to 500 mv and I get flat line on version 5 and tops chopped off on version 4. So what's up? Me or the scope??? Thanks for your help!!!

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kwinn

A schematic and/or waveform (with voltages) of the input signal would be helpful. It may be that the signal voltage exceeds the maximum input range on 500mV setting on Version 4, and the time base setting is too short on Version 5.

Redd Dawg

Here's the image at 1 v and 500 mv taken over the piezo speaker on the rc circuit on pg 37 of "Understanding Signals". It's got me stumped...



Thanks

ps as does the proper attaching of images. I'm learnin'!!!

mdr

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Post Edited (Redd Dawg) : 10/22/2009 2:04:31 AM GMT

kwinn

It looks like the top of the waveform is clipping at the maximum voltage the ADC can handle. Only a guess, since I do not know what the analog input circuit looks like or the resolution of the ADC.

Redd Dawg

Thanks much. I'll play with it and see what's up. I'm pretty sure it's owner / operator error.....

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