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8 BIT turntable
Layout
encoding
gray encoding
using something like an array of reflective IR sensors
Gray code
a silkscreen on the round PCB bottom to encode the position using gray code
“to get a gray number only change one bit”
https://www.semanticscholar.org/paper/Design-of-absolute-encoder-disk-coding-based-on-n-Paul-Chang
components
a few approaches on the hookup
DC motor
simply connecting a dc motor to the spinning disk
by rotating the disk you convert the energy to analog input for MCU or whatever
problem with this approach it will not give enough output at slow speeds. so probably scratch that.
Stepper motor
same as with the DC motor, you connect the motor to the disks center, then hook the stepper winding A1/2,B1/2 to an MCU, you get a nice stepping encoder.
following links are actually to use the sinusoidal wave of the stepper, a bit of a different approach
also a problem at low speeds.