GDS-820S Oscilloscope & Labview

[cevert73]

Hi all,

I'm new to labview and have recently been trying to record voltages from a constant temperature hot-wire anemometer for wind tunnel tests sampled at 10kHz for 10 seconds.  This data is recorded using a USB-6009 DAQ and while the mean voltages look good the rms (largely what I'm interested in) to noise is poor.  In order to diagnose where the noise is coming from I have been using a GDS-820S oscilloscope and eliminated suspects one by one.  There is a program, called freeview, which I can use with this oscilloscope to display what is on the screen, through a USB connection, but I think there is supposed to be labview compatibility to record the data, which so far I have not managed to get working.  I believe the problem may be the interface I've been using so far, perhaps I should use RS232 instead of USB but having searched the forums I haven't found anyone else who has used this oscilloscope with labview.  So I wondered if anyone could provide me with some advice as to how I install the drivers (available from the manufacturers website) and in what format could the voltages be written?  I've seen an example vi "basic serial write and read" but we don't own any of the required hardware to get some data to write out.

Thanks.  

[GovBob]

You can find the LabVIEW driver for that scope at their website. Unzip it into your Program Files>>National Instruments>>LabVIEW ???>>instr.lib . It should come with an example. Read the tutorials at the bottom of this page for information on how to use an instrument driver.

[cevert73]

Thank you for your reply and it is Labview v8.5 which we are using.  Would you (or anyone else perhaps) be able to inform me as to whether or not a serial to usb adapter could potentially be used, hence interfacing with the pc via usb?  The reason I'm asking is so that I can use a laptop for the purposes of this test, avoiding the trouble of moving equipment around the wind tunnel.  Furthermore this could be more purposeful than a serial f-f cable, that said it would do much harm to have both.

Thanks and I'll let you know if I can get it to work.

[GovBob]

Yes a serial to usb adapter should work. However you need to do some research as to which model/brand of adapter(s) work. People have had varying degrees of success with these adapters.

I have used a Tripp-Lite model U209-000-R with success in the past.

If your oscilloscope was purchased with the GPIB option I would personally use that. I would purchase NI's GPIB-USB adapter. (Note: I don't work for NI). My experience has shown that GPIB is superior bus than serial for this type of communication.