In the Quantum article at the top of page 5 there reads:
Surely this "1.2 micro seconds" is a typo?
Even at the highest observed frequency that was stated (i.e. 200kHz), 1.2us only samples 24% of one complete cycle, and gets worse at 143kHz. How can one get a reasonable average by sampling only 24% of one cycle?
Then there's this from page 6 of the EIT paper:
If as stated in the article that the aperiodic oscillation fluctuates between 143kHz and 200kHz, how can one obtain a reasonable average by only sampling a total of 10us (1us/div x 10 divisions) on the scope? To get at least one cycle of 200kHz and one cycle of 143kHz, would require a minimum of 12us. Also, the sampling time (10us) is on the same order as the period of the measured signal. For a uniform stable wave form this might be fine, but for a variable one such as described, several "mixed" cycles should be sampled.
Without observing the true nature of the described wave forms, it's difficult to prescribe an exacting mode of measurement, however knowing that it is unstable and aperiodic does support and even demand the use of a much wider sampling window to obtain an accurate average.
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In order to evaluate a reasonable average of the energy delivered, a sample range was chosen spanning 1.2 micro seconds.
Even at the highest observed frequency that was stated (i.e. 200kHz), 1.2us only samples 24% of one complete cycle, and gets worse at 143kHz. How can one get a reasonable average by sampling only 24% of one cycle?
Then there's this from page 6 of the EIT paper:
As mentioned, the voltage waveforms that result from such a high oscillating frequency vary greatly from one cycle to another. The transient voltage spikes that are deliberately generated, then compound this variation. In order to evaluate a reasonable average of the energy delivered a time base of 1us/div was chosen.
Without observing the true nature of the described wave forms, it's difficult to prescribe an exacting mode of measurement, however knowing that it is unstable and aperiodic does support and even demand the use of a much wider sampling window to obtain an accurate average.
.99
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