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2.715 + 0.425/2 = 2.9275 ms would be the “true“ speed then we have a +- of 0.2125ms or +-7.25%
the delta looks to be similar when applying 4V and 3V respectively.
Note that this measurement is using an envelope function on the scope so 7.25% would be between two magnets on the wheel, the actual delta between adjacent magnets can still be better.
Bench test 100% speed
The rc car was placed on the bench an a cylindrical magnet was attached on the wheel and the sensor mounted just next too it. The motors was supplied with a constant 5.5V and left for ~5sec until the rpm settled.
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