I would like to build an automatic water faucet, but wasn't sure what the sensor in a unit like the one below consists of. Here is a sample picture:
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What kind of sensor do these faucets use? Would it work well outside? I'm thinking of building an automatic water fountain for my dog which would consist of mostly everyday parts. The goal is to take a sink fixture and mount it upside down or sideways so the dog can reach it easily. The water source would likely come from inside and be slightly elevated from the exit point. The reason is so that once the valve has shut off the water will drain out and prevent freezing.
TIA,
-Inet