Super Mario Bros. on real Sega Mega Drive, what kind of sorcery is this? - CRT - Sony PVM-9045QM

What kind of sorcery is this? It seems to work as well. I just bought this "thing" thinking it was a rip off, but it really works. Seems to be a fully functional porting from NES, running on real hardware 1990 PAL Mega Drive. Just the sound is a bit strange, because Mega Drive audio synthesizer is very different than the NES one.
Monitor Sony PVM-9045QM