Ventspils International Radio Astronomy Centre (VIRAC) has two fully steerable Cassegrean System 32 and 16 m radio telescopes. After renovation and modernization program the Galactic masers, particularly CH3OH research and monitoring program became one of the most important realized on these telescopes. Both telescopes are equipped with broadband cryogenic receivers covering 4.5-8.8 GHz frequency band. Digital backend consisting from DBBC-2 (Digital Base Band Convertor developed by HAT-LAB, Italy) and FLEXBUFF (data storage system based on commercially available server system) is used for data digitalization and registration. A special program complex for spectral line data reduction and correction was developed and implemented.

We report another 6.7 GHz methanol maser burst in the high mass star region G33.641-0.228. The flare is in its second component at vLSR = 59.6 km s−1 and was observed in August-September 2016 by VIRAC radio telescope RT-32 in Irbene, Latvia. Several bursts of the second spatial component of G33.641-0.228 have been reported previously by Fujisawa et al. The maximum peak flux density of the source was measured to reach 343 Jy that is 13 times increase from its ground level. Significant oscillations were discovered during the decay phase indicating a more complex burst mechanism that cannot be explained by a simple heating of the region.