Something is not right with that display, the signal on it or the software coding. It is symmetrical around the center of the display. It looks like an amplitude modulated signal. A spectrum display of a regular audio signal is not symmetrical.
@tpo828 You're right. This is maybe cause the ADC mirroring (because of wrong parameters) but it'll can also happens if there's the dsPIC30 DSP library used with the 512 points FFT and a ADC speed of =<39062. Check your code. You're FFT signals are totally wrong! Check out how you need to read out the fractional sigCmpx[i]!
hi can you please send me the c code . mcp please?
MrRadicalinos 8 months ago
hi please can you share this code .c , i hope to test it thanks
MrRadicalinos 9 months ago
Something is not right with that display, the signal on it or the software coding. It is symmetrical around the center of the display. It looks like an amplitude modulated signal. A spectrum display of a regular audio signal is not symmetrical.
tpo828 2 years ago
@tpo828 You're right. This is maybe cause the ADC mirroring (because of wrong parameters) but it'll can also happens if there's the dsPIC30 DSP library used with the 512 points FFT and a ADC speed of =<39062. Check your code. You're FFT signals are totally wrong! Check out how you need to read out the fractional sigCmpx[i]!
turbojohnyS 1 week ago