From the first ever glimpse of Neptune transmitted by Voyager 2 in 1989, to the base stations used every day for our mobile phones and antennas, the High Electron Mobility Transistor (HEMT) was instrumental in allowing broadcasting-satellite systems to spread around the world. In his fascinating talk, Dr Mimura will explore the succession of events that led him to invent the device and how this achievement changed the worlds of both information and communications technology and physics studies of electrons.