They found that there's this GirlTech device used for texting that happens to operate at the same exact frequency as the P25, and they built what they called My First Jammer.  If you look closely at this device, it's got a switch for encryption or cleartext.
他们发现有个叫GirlTech的信息设备 所使用的频道和 P25 是一样的， 然後他们建造了一个叫 "我的第一干扰"。 如果你仔细看这个设备， 这里有个开关可以切换加密或是明文。