spectrum uncontinued signal

[ufo900]

So:

the single point is extracted by the index array that returns x(0;0).

I see the "history" rectangle (ps/psd and spectrum ok): what does it do exactly? I see the labview help but don't know what it does exactly do..

[johnsold]

The "history" rectangle is a Property Node. Property nodes are associated with a front panel control or indicator.  In this case the property node returns the history values for the Temperature chart. I named the chart so that I did not have an unlabeled property node on the BD.

Look at the Detailed Help for a chart to learn more about its internal buffer (called History).  You set the chart history length to 100 so you already know something about this.

The History property node allows you to read that buffer. The output will be an array with the last 100 values written to the chart. You can use these as the input to the spectrum VIs.

Lynn

[ufo900]

Thank you very much.

Just to know for the future: how to create that property node?

Tomorrow morning I'll report here 🙂

[johnsold]

Pop up on the control or indicator and select Create >> Property Node >> History Data from the pop-up menu.

Lynn

[ufo900]

Thank you.

Tomorrow I'll report here 🙂

[ufo900]

I think it's working, but do you advise to intepolate the values before doing the Spectrum Analyze?

And.....

I have some issues to apply PID into my system..

I can do a PID control by simulating a system only in temperature but issues if I want a voltage control that depends of temperature value.

Attached here PID subVIs I use and the program with the other subVI.

Hope you can help me apply PID into it.

Thank you

[ufo900]

little up

[ufo900]

now: spectral analyzer works (i think) but i need to filter the signal.. The spectrum has 30 frequency or more but i want only the temperature frequency..

How can i do that?

vi attached

[FatBoyMonchi]

Hi Ufo,

if you right click on the block diagram and go under Signal Processing menu, you can find the filters menu.

Also se the LV Example Finder: there are many exaples to understand how to use filters.

Hope it helps,

FBM