The acquisition and conversion of a continuous-time analog signal into a discrete-time digital signal is based on the sampling rate with a value range limited by the bit-rate. The range of values (point height) on a spectrum based is dependent on the bit rate 2^n. For example, a 12-bit ADC can represent values from 0-4095. The number of points or samples recorded in time (width between points) is based on the sampling rate (Fs). 1000 Hz represents 1000 samples per second. The nyquist theorem states that the sampling frequency must be twice the frequency of the highest-frequency signal observed. Anti-aliasing filters condition the analog signal before the ADC input with unity gain in the pass-band and strong attenuation in the stop-band to mitigate the sampling of unwanted high-frequency signals.