Maximum Overhang?

[jsondag]

I tested this with just a multimeter as a proof of concept. I just dangled one probe in the water, and touched the other to the foil. Seems to work, and level of salinity has no effect whatsoever. I went from a weak salt water, to more than double the salinity, with 0 change on the meter. My meter clearly doesn't have enough resolution for fine detail, I never expected it to. A RC circuit on an arduino should give very high resolution, as you're converting capacitance to charge time, and time is something micros are very good at measuring.

I used HVAC foil tape, in both a thin strip and wider one. I've found that a wider strip gave me greater movement in readings. I also found that the surface tension plays a role, as you move up and the walls get wetted, if you move down there is backlash, because you're measuring how far up the wall is wetted basically. No big deal for measuring only one way.

I'm attaching a graph of readings at half centimeter intervals. (nF on the left, cm on the bottom) and a pic of my test container.

My meter is not high quality or very precise, so the little variation from linearity is most certainly from that.


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