Hello, I'm designing a PLL for frequencies between 68khz and 72khz. It works wonders with SFFM signals, and now I'm on the stage of testing it with wave files from Scilab.
I made an FM modulation with 70khz carrier, I double-checked that the signal was correctly modulated. But when I import this signal to LTspice, I get something really weird on the signal FFT.
It's like the frequencies around 70Khz are doubled around 80Khz. I'm starting to think is a problem with LTspice. Does anyone have an idea of what may be going wrong? I also analyzed the spectrum of the signal on Audacity, and the peaks around 80Khz arent there, LTspice is for sure adding them.
I uploaded an image of the spectrum on spice.
Thanks! Sorry for my bad English btw.
I made an FM modulation with 70khz carrier, I double-checked that the signal was correctly modulated. But when I import this signal to LTspice, I get something really weird on the signal FFT.
It's like the frequencies around 70Khz are doubled around 80Khz. I'm starting to think is a problem with LTspice. Does anyone have an idea of what may be going wrong? I also analyzed the spectrum of the signal on Audacity, and the peaks around 80Khz arent there, LTspice is for sure adding them.
I uploaded an image of the spectrum on spice.
Thanks! Sorry for my bad English btw.
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