Abstract: A device for testing an electric circuit or components of this circuit provided on a board (9), which board (9) is secured against a support (7) by an underpressure in a first chamber (15) during operation. An electrical connection is effected between the board (9) and an electronic test unit (69) of the device by means of a contact plate (81). The contact plate (81) is provided exchangeably on a partition wall (13) which hermetically seals off the first chamber (15) from a second chamber (17) and which can be moved in a direction transverse to the board (9) by a pressure difference between the two chambers (15, 17). The exchangeable contact plate (81) corresponds to the type of board (9) and activates a combination of test probes (49) from a set of test probes (49) provided in a matrix plate (45), which combination is unique for the type of board (9), after the partition wall (13) has been moved.