[Dr_C2]

   

Here is a tacho pulse from one of my brushless motor driver boards. The sensored brushless motors contain three Hall sensor ICs at 120 degrees separation and each detects North and South poles as the fixed magnet rotates. The tacho pulse can be read from any of the three Hall sensor ICs.

This motor is 2-pole and in the photo is running at 747 rotations per second i.e. 44800 rpm.

As discussed elsewhere a tacho signal could be quite useful for digital slotcars.

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