Sand and electronics usually go together only slightly better than if you were using water, but this electronic sand timer seems to be an exception, if only in name. That aside, no sand was used in the construction of the device… unless you count the silicon in the electronics, which would entirely negate the previous sentence. However you want to classify them, these gadgets take the place of hourglasses in board games, representing a major improvement over their non-electronic silicon cousins.
One improvement is that these units don’t need to somehow be physically reset by draining sand from one end to another. You simply press a button and it starts, blinking a green LED progressively faster, then a red light for around 20 seconds when done. They’re also incredibly compact, fitting inside the same footprint as the mechanical type — approximately the size of a quarter — while being much shorter. Speaking of that, perhaps the most impressive thing about its product listing on Tindie — $22 for 6 units — is the image of its PIC10LF320 microcontroller. This is dwarfed by a grain of rice, and makes George Washington on the quarter on the other side of it look like something from Easter Island.
The electronic sand timers run on included coin-cell batteries, which can power them for years at a time. Timers can be configured to finish after between 15 seconds and 3 minutes, and when you finally do have to change the batteries, it will still remember your settings.
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Author: Jeremy S. Cook