A corrosion testing device includes a test chamber (10), a climate conditioning system (12) for maintaining a controlled atmosphere in the test chamber (10), and a measurement system including a feeler (16) having a measurement element (24) arranged on a printed circuit board (22) for measuring the moisture content of the atmosphere, in which the printed circuit board (22) is detachably held on a feeler base (18) via plug connectors (28) and is, with the possible exception of certain contact or measurement surfaces, fully encapsulated in an anti-corrosion coating.