It does, however, require calibration. [Jonathan] measured a known capacitor for a baseline, and used that data to calculate the stray capacitance in the Arduino.

Another common makeshift capacitor is a length of coax with connections at one end and open at the other. RG-8, for example, is about 30 pF per foot of cable.

Making a servo tester using an Attiny85 micro chip, Attiny45 also works for this project. This diy servo tester is as good as ...

Board have high effective step up converter with operation to 0.3V, because caps are are charged to 2.5V and then are discharged to zero. Features of the Arduino Watch include : ...

Decoupling directly from the 5V Vcc leg to the 0V plane is important – with more than one value of ceramic capacitor if possible (usual guidelines apply). I would probably carve out a little rectangle ...