A look at an ultrasonic "tapeless measure" that I won in a raffle many years ago. Spoiler: it's fun to play around with, but the lack of accuracy and short backlight/auto power off timer hamper its usefulness.
You can select between Imperial ("English") and Metric units of measure. The shortest claimed distance it will measure is 20 inches, and the longest is 30 feet. With care, I've gotten it to measure a foot and seven inches, one inch less than the minimum spec.
I set the clock about a week prior, but by the time I made this video, it was already 11 minutes out. It was actually closer to the correct time when I rediscovered it after sitting for all of those years! This probably has a lot to do with that long expired nine volt battery having dropped to a terminal voltage of just seven volts. On the plus side, that would suggest this thing will get all the average battery has to give.
(I did put in a new battery. Measurement accuracy did not improve.)
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