> You are still sampling at 1KHz to find the peaks, right?
> The 1.2% error I mentioned comes from the 1KHz samples
> missing the peak by as much as 500uS.

>From what I've read, he needs to reconstruct the sine with that
precision. That's about statistic, peaks does not matter at all. 1000
samples per second in the course of the very slowly (tenths seconds)
changing parameters of the sine signal - that's much more than just
enough to figure out the sine with the precision.
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