Computer Oscilloscope Problems

I've downloaded two computer oscilloscopes, so that I could measure the frequency of a two tone audio signal I have on a cd. Both of these computer oscilloscopes use the sound card for input, yet no matter how much I try to get them to measure the signal, all I get is a flat line, no measureable wave at all.

The one is Oscilloscope 2.51, the other is the BIB Lab Oscilloscope 3.0. Is anybody familiar with these two programs, and can give advice on how to set them?

Thanking you in advance...........DF

You may have to go into your mixer controls and uncheck "mute" on either the line input or mic input, whichever you are putting the signal into. Double click the volume control in your taskbar to get the mixer.

Looking at the Windows Mixer/Volume Control settings (go to options->properties, select recording. This may vary depending on which version of Windows your running) is a good idea, but you may want to back up a bit. Since it's already on an audio CD, you can directly copy it to your hard disk with a CD 'ripper' program. Then you can load the .wav file into any audio editor program and set it to display FFT to see the frequencies present at any point in the file/recording.

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