Sound Input using Sigmatel Audio 9200

[letreca]

Hi, I'm using the "Sound Input Read.vi" to aquire a analog signal from the Sigmatel Audio 9200 input. I'm using a Kistler Charge Calibrator to generate a square Waveform (0,5Vpp). When I measure the signal with a osciloscope, I can see a perfect square waveform. But, when I run the VI, I can't see the perfect waveform. I thought that the problem was happening cause I used a stereo cable, but I changed it to a mono cable and the problem continued happening.

Has somebody any suggestion?

[mishklyar]

Hi,

 What do you mean by "can't see the perfect waveform"? Is it exists?Is it noisy?

What is it freq? What is the sampling rate of the sound card?

Regards,

Michael

[letreca]

At the attachment you can find the wrong waveform that I can aquire. The frequence is 27,7 Hz.

[mishklyar]

Hi,

Datasheet of the soundcard:

http://www.idt.com/?genID=STAC9200&source=products_genericPart_STAC9200

it's written there that the lower limit is 20 Hz.If it is about a sine wave,than probably your square wave has too low

freq. for this card.I would try to rize the freq. and see if the picture goes beter.

Regards,

Michael