Frequency Issues
Hello!
A friend of mine ran my Cyton's raw data through Matlab and came up with some strange observations:
Rather than a "mains" peak at 60Hz, it was at what appeared to be 62Hz.
I also tried injecting known frequencies to see the effect, and we observed that the farther from 0Hz we got, the greater a positive shift in frequency. e.g.:
injecting 10 Hz gave 10Hz
injecting 20 Hz gave 20.5 Hz
injecting 30Hz gave 31Hz
injecting 40Hz gave 41.5Hz
injecting 50Hz gave 52Hz
injecting 60Hz gave 62Hz.
Is this soft of "frequency shift" common? We've tried trouble shooting where this may have come from but can't figure it out. Any insights or things to try would be greatly appreciated!
A friend of mine ran my Cyton's raw data through Matlab and came up with some strange observations:
Rather than a "mains" peak at 60Hz, it was at what appeared to be 62Hz.
I also tried injecting known frequencies to see the effect, and we observed that the farther from 0Hz we got, the greater a positive shift in frequency. e.g.:
injecting 10 Hz gave 10Hz
injecting 20 Hz gave 20.5 Hz
injecting 30Hz gave 31Hz
injecting 40Hz gave 41.5Hz
injecting 50Hz gave 52Hz
injecting 60Hz gave 62Hz.
Is this soft of "frequency shift" common? We've tried trouble shooting where this may have come from but can't figure it out. Any insights or things to try would be greatly appreciated!
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