| 摘要 |
<p>1. Apparatus for the non-destructive testing of articles by eddy-currents comprising an excitation generator (10), a probe (14) connected to said generator, the probe having therein sampling means for a measurement potential (Vm) corresponding to an article being tested generating, means for a reference potential (Vr) corresponding to a standard article, a differential amplifier (20) having first (20/1) and second (20/2) inputsand an output, the first input receiving the measurement potential and the second receiving the reference potential digital signal-treatment means (24) having an input connected to the output of the differential amplifier (20) a cross and amplifier (22), said treatment means comprising in succession an analog digital converter (30), a first direct-access live memory (32) and a digital treatment circuit (34) characterised in that the generating means for the reference potential comprise a second direct access live memory (40) having an input (39) and an output (42), the input being connected to the output of the first live memory (32) across an interrupter circuit (37), and a digital-analog converter (44) having an input (43) connected to the output (42) of the second memory (40) and an output (45) connected to the second input (20/2) of the differential amplifier (20).</p> |
