Patent ID: 7653500

Claim:
A method for correcting for errors in a sequential sampling timebase for use with an acquisition system of a test and measurement apparatus, a sample time for the sequential sampling timebase being defined by a time duration of a combination of a fine analog delay and coarse delay determined by the counting of digital pulses of a stable clock, wherein the value of the fine analog delay is held at a substantially constant nominal value during the duration of the counting of the digital clock, comprising the steps of: measuring a time difference between a trigger at which the fine analog delay starts measuring time and the occurrence of a digital pulse of the stable clock being used to count the coarse delay; sampling an input waveform at a sample time having a nominal delay time; providing a desired compensation time for the sample of the input waveform in accordance with a plurality of combinations of three independent variables defining a calibration table, the calibration table having independent variables including the time interval defined by the fine analog delay, the time interval defined by the coarse delay, and the time interval measured between the trigger at which the fine analog delay starts measuring time and the occurrence of the digital pulse of the stable clock being used to count the coarse delay; reconstructing the waveform by shifting the delay time of sampled value of the input waveform from its nominal delay time in accordance with a value defined by the calibration table; and storing the reconstructed waveform to a computer readable medium.