hardware/software requirement query...

[kirkland4]

I am analyzing frequency patterns from FFT's of a given signal.

I currently have a transducer running to an amp and ending in an oscilloscope that I use to create the FFT and analyze, all connected with BNC. I'd like to program LV to do this for me.

I believe that I need a DAQ board and then perhaps some NI-DAQ software (acoustics and vibration toolkit?). I need clarification on this. Mainly I'd like to know if I need some sort of analog to digital convertor before plugging into the DAQ board, and which DAQ board best suits my BNC requirement.

Thanks

[Henrik_Volkers]

Why not use your scope for your DAQ?

You didn't name the model but I assume that a scope that can do a fft will have a USB/RS232/488 connector and your chance is high that you get a LV driver to read your data.

[kirkland4]

im using a lecroy waverunner-2, I will check to see if it has usable ports, though I don't think it has usb

Message Edited by kirkland4 on 06-22-2006 02:40 PM

[kirkland4]

im using a lecroy waverunner-2,

[Ryan_V[DE]]

kirkland,

As Henrik stated, connecting through USB / Serial / GPIB is always an option with your current scope. If you do wish to purchase any NI hardware, which does offer easy, consistent programming through NI-DAQmx, perhaps you could provide a bit more information on the nature of the signals you intend to measure. What is their amplitude? Frequency content? Do you need to perform any signal conditioning? Do you want plug-in hardware, or a more portable USB-based solution. LabVIEW can perform basic spectral measurements and signal processing, but if you do intend to perform application-specific sound and vibration measurements, then the Sound and Vibration Toolkit would be right for you. Please let me know, and I would be more than happy to provide a recommendation.

Regards,

[Justin_M]

Hi kirkland4,

There are lots of different options when it comes to choosing the right DAQ card.  Much depends on the sampling rate you need, the resolution, the number of channels, etc.  I highly recommend taking a look at our M-Series DAQ devices.

If you need BNC connectivity, you can use one of our terminal blocks with BNC connections:

BNC Terminal Blocks

As Henrik suggested, you can also communicate with your external instrument using an instrument control device such as a GPIB card:

GPIB(IEEE 488) Solutions

There are many instrument drivers already available for download from NI.com, and I did a quick search for Lecroy drivers.  See the following results:

Instrument Driver Network

I hope this information helps!

Thanks,

Justin M.
National Instruments

[kirkland4]

Thanks for your replies.

data is at low frequency (100 k hz)

I am going to order a DAQ card eventually, but in the mean time I am going to run a GPIB to USB converter from my oscilloscope.

However, tinkering with labview I've found that I don't have the software extension that allows for the various FFT VIs? what package must I purchase or what package might I alrady have that contains what I need?

[Henrik_Volkers]

What package of LabVIEW are you running?  

[kirkland4]

I'm on labview 8 and I've got tons of extensions...Vision, NI-DAQ, motion, switch etc.

[Ryan_V[DE]]

kirkland,

This page compares the different versions of LabVIEW. It sounds like you may have the base package. The extensions you describe... Vision, NI-DAQ, and Motion, are our freely available drivers, compatible with all LabVIEW packages.

Hope this helps,