3 ms·Hmm, but how do they make sure the strobe is strobing at the right frequency?by netsharc 4y agoHmm, but how do they make sure the strobe is strobing at the right frequency?beAbU 4y agoMost likely the 50/60hz mains frequency?kqr 4y agoAs someone else said, the trick is that you can use a slower source to line up the rotation of a faster source to high accuracy. The idea is similar to that of the Vernier scale.