The Continuous-Discrete Sampling Demo is a program that shows the continuous and discrete spectra (and signals) during sampling. Continuious to Discrete The Continuous-Discrete Sampling Demo shows the continuous and discrete spectra and signals during sampling.
Do This:

1. Adjust the input frequency f0. What happens when it reaches half the sampling rate, fs?
2. Continue to increase the input frequency f0. What happens to the output frequency when the input increates from fs/2 to fs?
3. What happens to the output frequency when the input increases from fs to 3/2 fs?
4. Based on what you have seen, what do you think will happen with the input increases from 3/2 fs to 2fs?