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Friday, 21 June 2002
Final Report
Colin K McCord
Figure 11.2.3f. Screen dump of scope program (sample rate = 1,000Hz, input wave = 100Hz sinewave 0-5V)
200Hz sinewave (0-5V) connected to CH1/AN0, see figure 11.2.3g (resolution 100 x 80, that’s 10 x 8
divisions), 0.5 divisions per cycle, hence the calculated frequency of this waveform is 1/(0.5 * 0.01) = 200Hz.
But waveform is under sampled and heavily distorted, recall that the pulse interpolator display type
(scope.exe uses this) requires at least 10 sample / cycle before a recognisable sine-wave can be plotted.
Figure 11.2.3g. Screen dump of scope program (sample rate = 1,000Hz, input wave = 200Hz sinewave 0-5V)
500Hz sine-wave (0-5V) connected to CH1/AN0, see figure 11.2.3h (resolution 100 x 80, that’s 10 x 8
divisions), something real strange has happened here, clearly the result of under sampling.
EEE516J4 – Honours Project
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Chapter 11: Test Results