Grass Valley USA, formerly known as the Grass Valley Group, announced Monday the appointment of Tim Thorsteinson as the company’s new president and CEO, effective immediately. Thorsteinson has held numerous senior roles in the broadcast technology industry, including as the former President and CEO of Grass Valley LLC, which was founder in Grass Valley in 1959 by Dr. Donald Hare. The company currently lists San Francisco as its headquarters on its website. horsteinson has also been President of the broadcast communications division of Harris Corp., and president and CEO of Leitch, which Harris Corp. acquired in 2005. Most recently Tim …