JeremyCook
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•Created by aymen ammari on 12/6/2024 in #pcb-and-analog
What is the Optimal Electrode Shape for Non-Contact Water Level Sensors in a Coffee Machine?
Seems like I've seen moisture sensors using capacitive sensing, which is maybe what you mean by the RC oscillator. I probably wouldn't want to pass actual current from positive to ground through the water if that's what you're proposing (Maybe it would work, and maybe that is an accepted technique, but just my gut feeling).
For more info on capacitive sensing, you might check out this article I wrote some time ago about ATtiny touch sensing: https://embeddedcomputing.com/technology/software-and-os/ides-application-programming/attiny85-capacitive-touch-sensing-sans-external-resistors - The other thing that could be very useful shapes-wise IIRC is this Microchip capacitve Touch Sensor Guide (referenced there): https://ww1.microchip.com/downloads/aemDocuments/documents/TXFG/ApplicationNotes/ApplicationNotes/Capacitive-Touch-Sensor-Design-Guide-DS00002934-B.pdf - Has been a while since I looked at it, but lots of great info IIRC.
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