Setting the sample rate

[chrisharris]

Hi

I am using LabVIEW 8.5.1 with a PXI 6221, I am wanting to use labview to generate a sine wave of 10KHz with a peak to peak voltage of 15V. I am a little confused as to how I should set up my sine wave to achieve this. What samples per second and the number of samples should I use and should this be set to automatic.

This is probably more of a signal processing question but my knowledge of this is not the worlds best. Any help would be greatly appreciated.

Thanks Chris

[Norbert_B]

Chris,

first of all, the sine will not have offset? If it will, it is possible that you cannot use the 6221 to generate the signal since it only supports +-10V in respect to the ground level of the PXI system.

In order to generate an output signal, you have to create a waveform which represents the signal's shape. So you have to gather several datapoints which will shape your signal. For the output, you have to configure a speed for output of each datapoint.

So if you choose to have 10 datatpoints per period of the signal (which is suggested to be the minimum for a proper shape), you will have to configure an output "update rate" of 10 times of the frequency your signal should have. In your case: 100kHz.

If you choose to use 100 datapoints per peroid (improvement of shape information), the factor will increase to 100 times, so you would need a sample rate of 1MHz in order to get a 10kHz signal....

hope this helps,

Norbert

[chrisharris]

Hi

Thanks for your help, I am going to give that a try, I am also thinking that the rate at which the DAQ assistant recieves signlas from the simulated sine wave and sends them out might need to be adjusted. I will play around with it to see what I get.