Building a DIY stroboscope for measuring RPM

Stroboscopes can be useful for measuring the rotational speed of something that a tachometer cannot.
Arduino code, schematic and STL files:
drive.google.c...
Another strobe: • Building a Stroboscope
Music:
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[@JannieH]

I built this project. (I built three UA-cam designs, including this one.) I found this design is the best of them because:
1. Resolution is adjustable better than 1Hz, and can thus be really fine tuned.
2. Duty cycle is operator controlled. I can really obtain sharp images with this feature.
Thanks for the upload. It will be used to check the spindle speeds on my CNC router.

[@mofxikja1107]

Hello, I have a ready LED module, 20W but 12V. Can I connect an external 12V power supply to VCC without any problems?

[@Thaumatichthys]

It should be fine assuming the arduino's voltage regulator is an AMS1117 or something similar that can handle >12V.
Also, make sure the LED's average power isn't high enough to cause it to overheat, since in the circuit there isn't really any proper current limiting.

[@cheemsvan4768]

Could you tell me where your LED light is connected?

[@Thaumatichthys]

It is shown in the schematic in the description.

[@loganishere4760]

whats the max hz and what limits how fast you can pulse this

[@Thaumatichthys]

in the provided code it is limited to 31.250 kHz, though if you remove that limit it can go up to several MHz, at this limit it is the arduino's relatively slow clock speed

[@Raine_2407]

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