share imageIf you've ever seen a watch with a slide rule bezel and haven't known how to use it, we have a little guide for you.As many of you know, watches with slide rule functions have 2 logarithmic scales (the outer of which turns). In contrast, a tachymeter scale is hyperbolic and typically has numbers that run in from infinity down to sixty. Both slide rule and tachymeter watches use non-linear scales. Let's look a bit at a generic scale.
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