Before two seismic events with a magnitude of 5.0 occurring on Sep.14 and Nov.30

1999 respectively

several stations located on the ground and in the well simultaneously received the abnormal signals of electromagnetic radiation with different frequencies

forms and magnitudes. This paper analyzes the electromagnetic radiation signals during the process of weakstrongweakquiet variations before and after the earthquakes

and concludes that the abnormal information in electromagnetic radiation has the features of long lasting time

wide scope

strong signal

many information groups

decreasing signal and occurring earthquake in several days after a quiet period. At the same time

this paper tries to trace the wave direction by rotating the antenna direction of ULFⅢ ground electromagnetic information measurement equipment and changing the antenna location of DPJⅢ dotfrequency electromagnetic radiation instrument.