And the spinner was detected

I had some time to run my sensor on the real meter last night and was able to read the spinning disk with some reliability. It was not in full sun, so that test remains. I didn't drag my oscilloscope outside with me, so I don't know how close I got to saturation, but I am now hopeful. There was some noise in the output when pointing the sensor on the edge of the disk (it has a surprising number of imperfections). I had better luck moving the sensor above the disk and pointing it down.
The next step is to optimize the design by removing any unnecessary components, and cleaning up the output to produce a clean digital output. I also have to figure out how to mount the thing nicely.

I will be connecting the sensor to a microcontroller and sending the resulting data out via a wireless link to my main computer. The plan is to put the data on the web.

I created a first pass schematic including the microcontroller, I was able to route it all on one metal layer, which simplifies things from a manufacturing standpoint. This is important because I manufacture the boards myself, and have no plated thru-holes! I'll post the final design when I am done.