John, Can you elaborate on your "slideback sampling"? Googling, I can find that you mentioned it, but no detail.
I'm presently using a comparator scheme to find where the peak crosses a threshold.
But as you can imagine, this is effectively PECL running at nearly
5GHz... giving me grief on the bias lines, plus lots of BS to get from positive-rail-referenced to ground-referenced... for a complex AGC loop that measures tank losses in a VCO (that's as far as I can go in explaining ;-) ...Jim Thompson