To test the reliability of a testing apparatus which tests a large number of
objects
of the same type for one feature, generates a feature signal for each object and
checks the feature signal for fulfilment of a first condition, a test object is
conducted to the testing apparatus after a number of objects and the feature signal
of the test object is checked for the fulfilment of a second condition. The second
condition is that the feature signal of the test object corresponds to a previously
entered reference value. The reference value can be entered by storing the feature
signal of a test object as a reference value.
