You know what’s cool? Using your engineering knowledge to solve problems that you have while building something. This is exactly what [Reinis] did when his 3D printer’s endstop wasn’t working.
Many of us automatically go to a microcontroller when we run into a problem with a sensor, but often a simple analog filter will do the trick. The endstop in [Reinis's] RepRap style 3D printer was giving off an unusual amount of noise when closed. When he hooked the endstop up to his oscilloscope, he was shocked to see how much noise there really was. In comes the low-pass filter. Unhappy with the response time of his low-pass filter, [Reinis] solved the problem using a pullup resistor. Two resistors and a capacitor was all that he needed to fix the problem. A great solution!
How have you used analog filters in your projects? Send us a tip and let us know!