Hi all, I'm quite keen to have a go and make a rain sensing cicuit.
I have found this schematic online..
**broken link removed**
rather than have an irritating buzzer sounding I would like it to just switch on an led. What would be the best method of modifying the circuit for this purpose?
Yes, it decides about the resistance of the sensor plate - completely wet or just a few drops of water on it.
Rain water doesn't have the same resistance all over the world. It has less resistance in high density industrial areas (sour rain) as is has in the jungle - hundreds of miles away from any industrial facility
Also water from a well has a different resistance from rain water.
Example: My well water has a resistance of 50KΩ/cm while rain water here has double the resistance.
that sounds good being able to adjust sensitivity. I think I will give that circuit a whirl. Just wondering on the best method of making the sensor without using copper as I cant see copper lasting to long out in the elements
that sounds good being able to adjust sensitivity. I think I will give that circuit a whirl. Just wondering on the best method of making the sensor without using copper as I cant see copper lasting to long out in the elements
If you tin the copper it will last pretty long. Do not use chemical tinning. It will disappear pretty soon leaving the copper which then will get a coat of "patina". Patina won't be destroyed by meteorological influence, but might increase the resistance even when wet.
You can also make a sensor of stainless steel. Just cut small stripes and connect them as shown in the picture I posted. Stainless steel can be soft soldered if you use flux for soldering.