Originally posted by Mike Sulzer
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What Lemme's analyzer did (before eddy currents) is automate a standard test approach where one resonates the coil with a series of capacitors of known value, and mathematically solves for the added capacitance needed to make it come out right. This added capacitance was the self-capacitance of the coil, as the theory goes. The fly in the ointment was that the inductance varied with frequency due to eddy currents. I don't think he knew why his answers didn't quite add up, and just found some kind of workable average. Adding an adequate eddy current model would allow this same approach to give far better answers.
The apparent purpose of the article is to sell his pickup analyzer. While I don't doubt that it does exactly what is claimed, for that kind of money one can buy standard test equipment that can do more than one thing, including measure pickups.
I corresponded with him some years back. He was trying to convince me that a Maxwell-Wein Impedance Bridge could not be used to measure pickups, which is very interesting, as this is exactly what the various national standards labs used for at least a century, until digital techniques took over. Bridges were literally the gold standard.
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