Sandaysoft

this is not really a forecasting matter but....

With all these April showers it would be very useful to have something that caused a sound or flashed a square when the rain bucket tripped after a specified time to indicate the start of a shower.

It might be necessary to have a means of varying the interval since the previous trip and even the number of trips.

Would help me get the washing dry? (wh1080)http://sandaysoft.com/forum/posting.php?mode=post&f=16&sid=5c28a217d1c7b6895be2eab669879b19#

Hi,

You can set the hour or 24-hour rain "alarm" threshold on the WH1080 (and others) below a single-tip (e.g. 0.2mm) and it will indeed sound on the first tip. You probably need to use the Easyweather software to do this as it doesn't seem obvious which alarm is being set via the console.

However, 0.3 mm is quite a lot of rain so your washing will still probably get wet(ter). I tried using a large funnel above the gauge but it didn't make the "first tip" occur any earlier, because more rain drops collected on the funnel surface (due to surface tension) but didn't run down to the see-saw quickly enough. Maybe spray some WD40 on the surface?

If you want a sensitive detector, I think Steve posted a link to a capacitive sensor earlier this year, but it wasn't cheap.

Cheers, Alan.

you can build a cheap rain detector like this.
I will take a picture of the actual sensor and post it later.

as promised a picture of the sensor and circuit. Cost about $2.00

Hi,
If you're looking for a ready to go product (please note this is not an endorsement, I just saw it talked about elewhere) the KEMO M152 rain detector might suit your needs.
Do a google for suppliers, retails for ~£20.
Regards,
Bill.

Hi,

Yes, an interesting "hobby" project that could be quite useful (for example) if you still put washing out in the garden to dry. But IMHO two major weaknesses, it really needs an audible alarm, and must be cleaned of water once triggered. Maybe using "Veroboard" (copper-clad stripboard) could be more rugged. I see that the Kemo uses a heater to "reset" the device by evaporating off the water, but not very practical for battery operation.

More expensive, of course, but there's also the very interesting Hydreon RG-11 which can give continuous, unattended detection of "it's raining (or not raining)".

Cheers, Alan.