Spectra of solar microwave burst events

The two solar radio spectrometers of National Astronomical Observatories for frequency bands 1.0–2.0 GHz and 2.6–3.8 GHz were put into operation, respectively, in January 1994 and September 1996. Since then up to April 10, 2000, they have recorded, respectively, 297 and 316 solar radio bursts and acquired high-quality dynamical materials with high temporal and frequency resolutions. This provides abundant information for the study of the temporal and spatial evolution processes of solar flares on various scales. The event of 1998-04-15, which was observed with both spectrometers, displayed diverse changes of amplitudes and structures in both time and frequency.