@ryanc Doesn't take much practice, even. The mechanical decoders were notoriously tolerant. You'd just need to know how many ticks number 1 was, and whether the subsequent numbers were more ticks (common on the Northern heimsphere) or less ticks (which apparently was, for some reason, common in Australia). But the rotary dial didn't run the other way in Australia; the dial's direction is determined by the right-handedness supremacists. Only the numbers appeared in the opposite direction, because the proximity of a number to the finger-stop was mechanically coupled to the tick-count of the number.