The scope shots By comparing the two graphs, can we conclude that the RHS graph has much more area than that on the LHS?
It would be incorrect and unscientific to make any conclusions based on a visual comparison of those wave forms. High voltage spikes does not automatically indicate a large average power or energy. I believe it is irrelevant to talk about average, mean or rms once we have the Instantaneous Power Curves. The correct scientific value is in fact the integration or the area enclosed by the curve.
You noted previously that you accepted the fact that the average and integral ratios would be the same, and taking the integral is an unnecessary step. Now you disagree? Rose has even confirmed what I said, and admitted that I was correct about this. So to summarize again: 1) calibrate the scope channel prior to measurements. 2) obtain the instantaneous power using the multiply function in the scope to multiply channel 1 voltage by channel 2 current. 3) use the "mean" or "average" function in the scope on that instantaneous power trace to obtain the running average power. 4) compare the average input and output power values. Anything short of this procedure will produce erroneous results. Please don't attempt to make quantitative assessments based on a visual comparison of spiky wave forms, it's unscientific and prone to gross errors. .99
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