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censored parts

Hi

 

I need to implement a lock-in amplifier as part of a graduation project .(using PXI)

As a first step, i want to build a vi containing some of the lock-in common features, with  a few extra ones.

i've downloaded the lock-in startup kit and tried to use some of the vi's like the pll or demodulator but all i see is a big "censored" on

the front panel.

how can i use these sub vi's (or any other relevant) in my vi?

important note: my goal for right now is only to simulate the functionality of the lock-in, no DAQ or external hardware required.

 

thanx!

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You simply use them as subVIs.

 

The context help describes the functionality and connectors. Also observe how they are used in the included demos. A passworded VI can be used like any other subVI, it simply cannot be edited and inspected.

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The lock-in amplifier is basically a synchronous demodulator followed by a low-pass filter. A synchronous demodulator is made simply by multiplying your reference signal with your measured signal (caused by the reference signal). You multiply sample by sample, with the standard multiply function. A low-pass filter is also easy in Labview. A PLL can also be built in Labview. But I have never done it myself. But I have made a lot of synchronous demodulators. It is a toolkit called "NI Modulation Toolkit " I think this toolkit have PLL. Some Googling will give a lot of help. But I have also included some documents. You will also find a funny document here

http://www.cpm.uncc.edu/programs/LIA_Primer.pdf to big to send 

 



Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)
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Another reason could of course be, that NI have used some X-rated controls/indicators in this application. So instead of risking a lawsuit they choosed to censor some material. Who knows because I have never seen this kind of censorship in Labview before



Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)
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