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Lock-in Amplifier and DAQmx

I've downloaded the NI Lock-in amplifier toolkit (llb file), and I have a PXI-4472 board. The toolkit looks to be based on traditional DAQ, not DAQmx. Did I miss the DAQmx version, or has no application engineer posted one yet? Please let me know if there's a timesaver out there before I just start to convert it on my own.
Thanks,

Rob
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Message 1 of 29
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Here is the Lock-In Amplifier example library for NI-DAQmx.  This will go live as an EPD on Tuesday.

Thanks
Travis
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Message 2 of 29
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Thanks. That version doesn't work with LabView 7.0, by the way. I had a tech support person email me with a version that would.

Here's an update from my end: I have it setup and running. Only, it seems to burp at the PLL sub-vi. I KNOW that have the correct data going into that sub-VI and that my DAQ board is working b/c I've put probes and indicators in the path and such. The problem is that it doesn't calculate the correct reference info. If I place a probe at the "reference info" output, it returns a constant output of fr=1 and phase =0. This is bizzare. I've changed every parameter I can think of (sampling rate, block size, offset parameter, column value, time constant, etc.) but it yields no positive result.

Any ideas or suggestions? I'm at wits end.

BTW, my board is the 4462, not the 4472 I mentioned previously. And, my refrence signal is a TTL square wave from 0-4 Volts, operated anywhere from 10Hz to 2KHz. That's working correctly as shown by my scope. But according to the PLL VI, it is always 1 Hz!

Thanks,

ROB M.

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Message 3 of 29
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Rob,

Have you tried setting the function to "Square" for the LockInPLL.vi?

Thanks,
Travis
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Update: I know I have the PLL VI working properly. An app eng was able to figure out that something happened to the PLL VI when the sample was backwards-converted to operate to Labview 7.0. He's not sure why this occurred, but it was remedied with a simple cut and paste of the PLL icon from the traditional DAQ lock-in amp block diagram or the Labview 8.0 block diagram into the Labview 7.0 block diagram. B/C the PLL VI is password protected, there's no way of telling what happened to the VI in order to figure why it conked out.

So, just be aware that if you see this behavior in the DAQmx lock-in amplifier start-up kit, it might be due to LV version conversion issues, and it is easily fixed by the cut and paste of the VI for some odd reason.

Thanks for the help

ROB M.

Message 5 of 29
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     Could I have the password of lock in PLL.vi .
     Thanks
      Wei Zhou
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Message 6 of 29
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Hey Wei Zhou,

National Instruments does not provide the password for the block diagram for this VI because it contains National Instruments proprietary information. You shouldn't need the password to use these VI's.
Regards,

Chris Delvizis
National Instruments
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Message 7 of 29
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Firstly thanks Chris D,appreciate for your help.
I'm a newfish to LV.Lots of problems disturbs me.
At present ,I want to built a vi to detect the phase shift of two signal(200k or 1MHz) with the same frequency base on the phase lock loop.
I use DAQ PCI-6115,the version of LV is 8.2.The signal is generated by Tektronix AFG 3022.
I download a vi 'MultiChannel LockIn - DAQmx',but it couldn't detect the signals beyond 100kHz.
Waiting for your help.
Best regars.
 
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Message 8 of 29
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Hey Wei Zhou,

I am happy to help. The Lock-In Amplifier Toolkit was intended for use with DSA devices. The linked article below gives some details on why you are having trouble with signals above 100kHz.

Using the Lock-In Amplifier Toolkit in Applications Requiring Fast Sample Rates
http://digital.ni.com/public.nsf/allkb/0DF72DBB9811E7A586256F80006B9710?OpenDocument
Regards,

Chris Delvizis
National Instruments
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Message 9 of 29
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I have just bought a card 4462, I wonder this card could be used as DLIA solution? Thanks !
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Message 10 of 29
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