Comments by "SmallSpoonBrigade" (@SmallSpoonBrigade) on "Why it's not possible to synchronize turn signals (but also absolutely is)" video.

I take it he doesn't know anybody that's had to replace multiple flashers. My mother compulsively saves her turn signal clicks because her previous Chevy had to have the turn signal blinker replaced quite a few times. And my wife will turn off her turn signal if she's sitting in the left turn lane for very long, only to turn it on again when she starts moving.
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This is an interesting video, but you shouldn't expect to be able to sync turn signals unless there's a standard that requires them to blink at a specific rate. Otherwise, car manufacturers will choose whatever random rate it is that's cheap to use and it likely won't be calibrated between cars or models. Unless everybody decides to use the same frequency, you should expect them to drift a bit as they're just meant to attract the attention of human drivers.
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