# How to check the sampling rate of a Data Acquisition device?

I got a USB sampling DAQ device, which says it is capable of e.g. 100kS/s per channel.

How would I test if it is indeed capable of doing so? I don't seem to find any hints of where I'd start with that...

• Count the number of samples it outputs in one second? Commented Oct 25, 2018 at 8:52
• @PlasmaHH I know some signal goes in, lets say at 50KHz to be the maximum for that sampling rate. So I sample at 100kS/s. How can I see or calculate from whatever digital output I get out of the DAQ that the sampling rate was indeed 100kS/s? Like... what do I need to search for? I heard a mention of FTT but I don't know what I need it for or what it is..? I never used a DAQ and I have very limited knowledge about physics.. How can I get a graph and how do i count the outputs per second? Commented Oct 25, 2018 at 9:57

Use a function generator with a known frequency square wave, for instance 1kHz, and measure how many points you have on a full cycle, should be 100.

If you don't have a function generator, you can use a small optical sensor like photodiode or shorted solar cell and measure the flicker of the light, as it is a known 50 or 60Hz depending on the country you are in and count the number of points you have for a full wave.

• Lets say I have a file with all the outputs over 1 second where 100kS/s is the sampling rate, and I got a 50Khz square wave being generated. The equation for the amounts of idential points would be sampling rate / frequency of wave? So I'd get two points which are of identical voltage? Commented Oct 25, 2018 at 12:42