I challenge the music industry. Read the Gearwire interview about the optical pickup. This is the missing link for better understanding of stringed instruments.
Ron Hoag
P.S. This is not spam, I am retired and do not sell anything.
The input transformer of the inductor is necessary for the D.C. shift that will occur if the photo diode is exposed to higher light incident to the photo junction. If proper design is used, no cover or very little light cover is required.
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