In lowpass mode, the FFT size needs to be >= 2x the number of sweep points in order that DC, Nyquist, positive frequencies and negative frequencies fit into the FFT buffer. But the definition in common.hpp does not provide that many points. The models with SWEEP_POINTS_MAX=201 would actually require 512 points, not 256.
if SWEEP_POINTS_MAX < 256
define FFT_SIZE 256
elif SWEEP_POINTS_MAX < 512
define FFT_SIZE 512
else
error "Need update FFT table for more points size"
In lowpass mode, the FFT size needs to be >= 2x the number of sweep points in order that DC, Nyquist, positive frequencies and negative frequencies fit into the FFT buffer. But the definition in common.hpp does not provide that many points. The models with SWEEP_POINTS_MAX=201 would actually require 512 points, not 256.
if SWEEP_POINTS_MAX < 256
define FFT_SIZE 256
elif SWEEP_POINTS_MAX < 512
define FFT_SIZE 512
else
error "Need update FFT table for more points size"
endif