Test and Measurement Forum

Trying to determine frequency

Post your LabVIEW discussions here

Trying to determine frequency

Postby roastmeat » Wed Jul 03, 2013 4:01 pm


I am trying to determine frequency using the PS2005 using both channels @ 8064 samples (maximum value looped back to the dll) and a timebase of 1.

I have used this process before and it has worked, but on a different application.

I basically get the power spectrum and find the highest peak and determine what frequency that is.
I must divide the frequency given by the spectrum by a block size (seconds) to get the right value.

To find this, I used Sampling Frequency/# of samples, which is 100Mhz/8064.

The problem is, if I use a function generator (correctly calibrated with a seperate oscilloscope), I get a frequency that is off by about 0.01MHz. It changes nonlinearly as I sweep the function generators frequency from 1Mhz to 4Mhz. Accuracy to about 100Hz is necessary.

Am I doing this process correctly?
Is there an easier way to calculate frequency of the signal?
Is there a function in the dll files that will help me?
Posts: 0
Joined: Thu Oct 18, 2012 12:24 am

Re: Trying to determine frequency

Postby Martyn » Thu Jul 18, 2013 8:54 am

Have you tried running the Picoscope 6 software and using either the measurement, or maths channel options for Frequency to see what they give ?
Technical Specialist
Site Admin
Site Admin
Posts: 2314
Joined: Fri Jun 10, 2011 8:15 am
Location: St. Neots

Return to LabVIEW

Who is online

Users browsing this forum: No registered users and 1 guest