With the right device tuned to the right frequency, what's to stop a thief from jamming your setup and blocking that alert signal from ever reaching the base station?
通过将正确的设备调整到正确的频率，如何防止小偷干扰你的设备阻止警报信号到达基站呢？
2
Any distress vessel in the all sea areas may use DSC device working on different frequency to send distress alert.