creating square signal with sound card

[vdp]

I need to generate a square waveform signal, I wonder is possible to do this with a sound card. I need a signal with a low frequency (about 5-10 Hz). I need to know, are the sound cards with digital output (I think it's called SPDIF?) able to play this low frequencies?

 

[Crysalis]

I dont know of any soundcards that produce that frequency that aren't expensive. What you could do is buy a tone generator. It is just a standalone oscillator that plays back whatever frequency you want.

I may have a WAV file containing that low frequency. I think it only goes to 15hz.... could be 10 but i dont remember. If you would like that to burn on a CD, I could send it to you. Let me know