転換 | Usually used about machines or organizations, close to the English ‘conversion.’ All TVs in Japan will convert to digital in February. This devices converts ac current to dc. Also used about sex changes! Russia converted to capitalism. $$$ |
転向 | More used about personal things, changes in one’s lifestyle or politics. Often used about young people when they cut their hair and put on a suit., but could also apply to a dude with a mid-life crisis who drops out and lives on a house-boat. |