modifying the scale at a chosen frequency

[labsee]

hello,

i would like to center the frequency scale of my graph at a frequency that i chosed, but the scale is blocked between 0 to 125 khz and want to see it at 1420 Mhz, don't know if there is a problem with my program as i am new  with labview, thanks a lot for your help.

Here my diagram :

[Henrik_Volkers]

Dop you see the red dot at your FFT vi? (feeding a num array to a wfrm input)

The sample frequency is now assumed to be 1

to get the correct frequency scale you need to provide the sample rate (as time dt)  in the wfrm cluster, or do some math and scale your graph 🙂

 and why do you have the feedback nodes in the wire?

Are you playing with RTLSDR?

[ML927]

Hi Henrik,

If sample frequency was 1Hz, shouldn't the graph plot only values from 0 to 0.5Hz ? I agree that without dt the VI should lead to a sample frequency of 1Hz but it doesn't seem like it does. As the subject was posted on the French forum too, I tried to find an explanation but couldn't get any clue as of why it gives these results.

Any thought about that problem or did I miss something ?

Thanks in advance.

[labsee]

Hello sir,

thank you for your anwser, i am a student from france and i have a project with creating a rtlsdr system via labview to see the hydrogen ray  at 1420 Mhz.

I see the red point, but then i don't understand what i have to do, i am a beginner to LV so i don't understand where is the "wfrm cluster",  and how to do scale graph  using mathematics in LV.

Cordially

here is my program