如果所有的措施都不能避免RF干扰进入测试输入端，那么就可能需要在设备的输入通路上进行外部滤波，如图3 - 7所示。
If all else fails to prevent rf interference from being introduced into the input, external filtering of the device input paths may be required, as shown in Figure 3-7.
以微机联锁安全软件测试为例，提出了划分高速铁路微机控制铁路信号设备安全软件输入空间的一种方法。
This paper takes the Microcomputer Interlocking Safety Software as an example and illustrates a method how to classify the inputs of Safety Software in high speed railway.
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