You need to implement a comparator circuit with hysteresis, and you pull up some app notes. They look something like this, credit to Analog Devices:

comparator schematics

If you have a circuit in hand, there are a dozen or so discussions online to determine the comparator’s characteristics: high threshold $V_{TH}...

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This is probably something that would have been obvious to everyone else, but stumped me for a bit when I came across it the other day. I was looking at the rate of change of a sequence, and my smoothing algorithm wasn’t doing any better than just subtracting two points in the sequence farther ap...

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The basic steps for loading a Raspberry Pi image after downloading and unzipping the image (to /dev/sdg1 for example) are:

sudo umount /dev/sdg1
sudo dd bs=4M if=2013-09-10-wheezy-raspbian.img of=/dev/sdg1
sudo sync

This didn’t work for me. It seemed to write the data but left the card unbo...

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The A/C system of the Ford Escape has a resistive sensing element used regulate the blower motor. If you find that the A/C blows air on some fan speeds but not others, it is likely that the blower motor resistor has burned out or otherwise failed. On my 2009 Escape, the blower motor would run in p...

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