[g5pw]

I made a home-brew seismic sensor using something similar, a hard disk head arm assembly, a cd-rom laser (which has an anisotropic lens and four photodiodes) and a Red Pitaya used as PID, so I guess it can be done!

[pfdietz]

Oh man, this is giving me The Amateur Scientist vibes. What would C. L. Stong be doing with today's technology?