Bought in the bedroom for the purpose of moisture monitoring this device. It is small (even very small, only 52 x 39 x 15 mm). The display is still easy to read and the displayed values quickly adapt to the environment. At the moment I tend to 5 stars because of the simple and reliable function and price-performance. Since there is but one more thing:
I already have a weather station that indicates the relative humidity. The difference between the two devices makes exactly 25% (ie the weather station displays 25% RH to less). That is one of the two devices is lying and I will find out the truth :-) whether this review will remain associated with 5 stars, I'm dependent on the accuracy of humidity measurement.
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UPDATE 26/11/2011: For comparison I look at just 5 piece TFA 30.5005 a Päzisions-hygrometer and my "old" weather station. Am amazed every 5 TFA 30.5005 indicate the same data: 54% RH, 21 ° C. The hair hygrometer indicates 56% RH. The weather station 26% RH ;-) The weather station comes before the electronic scrap. The TFA 30.5005 are really very accurately (+/- 5% are the way specified by the manufacturer). Since you can not complain really.
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Even I do it depends on how long the battery supplied (1 button cell LR 44 / AG 13) holds.
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UPDATE 20/10/2012: The batteries last even a year so's for sure. I seem to recall that someone has these devices certifies a poor battery life. That's not true!
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UPDATE 05/26/2013: have today replaced the batteries, because the display has become pale. This means that the little things running around 1.5 years a small AG13 / LR44 button cell. That's not so bad.
