I think it makes sense that this broadcasting test would be conducted in Hitoyoshi because, as I understand it, some of the more remote, mountainous places in that region have ben unable to receive digital TV signals.
“Nippon Hoso Kyokai (NHK) Science & Technology Research Laboratories conducted the test from its bureau in Hitoyoshi, Kumamoto Prefecture, in southern Japan, and managed to send the 8K Ultra High Definition TV signal to a receiving station 27 kilometers away using a single UHF channel.”
http://www.pcworld.com/article/2089720/japans-nhk-tests-longdistance-8k-tv-broadcast-signal.html
