一九七六年七月二十八日唐山7.8级地震前若干天,从承德至塘沽,从渤海岸到北京、天津,包括整个唐山地区在内出现了大范围的电磁波异常现象.奇异的电磁波讯号像出没无常的“不速之客”闯入了发射与接收电磁波的各种系统中,搅乱了这些系统的正常工作,并涉及到日常生活中常见的收音机、电视机、半导体闹钟等.这些“不速之客”在大震前悄然而至,震后又不胫离去.下面举出一些比较典型的实例: A few days prior to the Tangshan earthquake of magnitude 7.8, July 28, 1976, a wide range of electromagnetic anomalies were observed from Chengde to Tanggu and from the Bohai Sea coast to Beijing and Tianjin, including the entire Tangshan area. Signal infiltrated “uninvited guest” breaks into various systems that launch and receive electromagnetic waves, disrupting the normal operation of these systems, and involves the daily radio, television, semiconductor alarm clock, etc. These “uninvited guest” Quietly before the earthquake, after the earthquake and shook away. Here are some more typical examples: