HP 4194a Analyzer LabView Libraries?

[UVaGradStudent]

Does anyone know where I can locate LabView Libraries for an HP 4194a Impedance/Gain-Phase Analyzer?  We've just purchased this fairly pricey instrument and it's relatively useless to us if I can't control it remotely to sweep frequencies and extract numerical signals.  Suggested alternatives would also be greatly appreciated.

Matt

[MWhitson]

I just tossed "4194a" into the search box on the top level of ni.com and came up with:

http://sine.ni.com/apps/we/niid_web_display.download_page?p_id_guid=E3B19B3E9528659CE034080020E74861

[Brian_Beal]

I have quite a bit of experience with the 4194a and Labview.  I don't use the drivers, though.  I use gpib commands.  Let me know what you want to do, and maybe I have something that will work.

[Brian_Beal]

Just to expand a little bit.  I use 2 methods to run tests on the 4194a.  One is send it the commands for the test parameters one at a time and get the results.  The other is to run a stored program on the analyzer and get the results. Either one works well in Labview, it just depends on your setup.

[UVaGradStudent]

Ah, yes, thank you.  By including "HP" in the search term I excluded the Agilent drivers.  I ended up calling NI support, and they sped me along to that link, but I'll remember your method for future searches.

[UVaGradStudent]

I typically use LabView to set the 'Start', 'Stop', and 'Step' frequencies, initiate a frequency sweep, and record the magnitude and phase (or complex impedance, I forget the format in which I collect this data) to a DAT file for further manipulation etc. with Matlab.  I have working VIs for the 4192a, but I haven't had much time since discovering the drivers to attempt modifying the code for the 4194a.  I'll take a closer look at this afternoon to see if I can get it working, but if your code is set up to do this, I'd be interested in taking you up on your offer.

Matt

Message Edited by UVaGradStudent on 01-20-2006 02:23 PM

[Adam_Stouffer]

UVaGradStudent, did you write your own vi for the 4192a analyzer? I am using the example vi to run frequency sweeps but would like to find a way to report the resonant frequency. I think this is because the 4192 only reports back the values measured and not what the current frequency is. It would be nice to see a spike on the impedance graph and also what frequency it occured. Also are you using visa or gpib calls? Thanks.


Adam

[Sam K]

I've been using GPIB commands to operate the analyzer, but I've been having some problems. Mainly, I'm trying to collect data from the analyzer by sending the commands X?, A?, and B? which return the results of those registers. However, sometimes when I send X? it returns the result of A? or B?. Does anyone have a suggestion on how to fix this error? I've tried clearing the registers before sweeping new data and waiting longer periods of time to collect the data, yet neither seem to help much. 

Thanks

Sam

[Crimmsy]

I too would like to use the NI VI to perform frequency sweeps for an upcomming test.  Currently I dont have a version of LabVIEW that is new enough to run this driver.  Once I do obtain an updated version, all I need is this driver? Do I need to do anything else so that data is saved in a DAT file?

[UVaGradStudent]

Adam - Sorry for my (extremely) delayed reply.  I did write my own VI for the 4192a - it allows me to specify the Start, Stop, and Step frequencies used by the analyzer.  It then uses those values to generate a vector of frequencies against which to plot the analyzer magnitude and phase data.  All information is then stored in an Excel spreadsheet.  I'd be happy to send it to you if you like.