| 摘要 |
<p>This system provides a visual and audible signal when the radioactivity reaches a predetermind level. A single G.M. detector tube is connected to the main apparatus at is not >50m away, by a long coaxial cable e.g. T.V. cable of 75 ohms and an internal electrical test system is provided in the circuit, to enable the operator to check the functioning of the apparatus. The input from the detector is integrated and the mean voltage produced applied to threshold circuit which drives the warning device. This method is simpler to use and highly reliable.</p> |
