Friday we got some rain. I was out in it, wiring up an RG-11 in drop counting mode to get a feel for how it works. It was pretty cool to see the OUTPUT LED flash every time it detected a drop.
The storm wasn't very varied in rainfall intensity, so I didn't get to make a lot of observations. I timed 10 drops on the counter at 1 minute, looked out the window and called it a light rain, and then checked the rain rate on my VP2 at about 0.25" per hour.
So there's a baseline to start playing with integrating drops into an analog voltage intensity value.
The RG-11 was set in 100 ms/drop counting mode since I didn't have a way to differentiate between larger drops/longer pulses in the other mode.
This experiment begins to reveal how the unit functions inside. I don't have the actual numbers at hand right now, but roughly 6,000 counted drops equaled 0.65" of rain.
When I was timing the drops, it took a longer that I expected to count up some consecutive drops. Empirically, for an hour while it was raining, I studied the rainfall pattern in a 7 foot square collector, as well as in a collector about the same diameter as the RG-11. It was interesting to see the size of the drops affect the size of the splash, as well as how few drops actually made it into the small collector for the intensity I perceived.
(Translation: I sat in the hot tub while it rained and drank a glass of wine.
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