RH Meter
Approx construction cost US$47
Uses a capacitive sensor to measure the relative humidity (RH) of air.
Although we consider air to consist of nitrogen, oxygen and a little carbon dioxide, one other component is essential for normal life, namely water. Too much or too little water in our atmosphere soon leads to discomfort and even serious health problems.
Static charge build-up with all its consequences is directly related to low humidity. Air humidity also has large effects on many engineering and building materials in everyday use. The RH Meter (Hygrometer) described in this project uses a new capacitive RH (relative humidity) sensing element to give an accurate measure of the relative humidity of air.
More details on this construction project can be found in the March 2002 issue of EPE Online, the world's first web-delivered electronics and computing hobbyist magazine.
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