Metric Radio Bursts and Fine Structures Observed on January 20, 2005

A major radio event, associated with an X7.1/2B flare in AR720 and a fast CME was observed on January 20, 2005 with the radio-spectrograph ARTEMIS-IV; it was particularly intense and with a complex radio signature with rich fine structure which was recorded in the 270-420 MHz range at high resolution (100 samples/sec). The fine structure is compared with similar results in the decimetric and microwave frequency range. It was found to approximately match the comprehensive Ondrejov Classification in the spectral range 0.8-2 GHz.