Zenith Electronics, LLC is a research and development company that develops ATSC and digital rights management technologies. It is owned by the South Korean company LG Electronics. Zenith was previously an American brand of consumer electronics, a manufacturer of radio and television receivers and other consumer electronics, and was headquartered in Glenview, Illinois. The company was co-founded by Ralph Matthews and Karl Hassel in Chicago, Illinois, as Chicago Radio Labs[4] in 1918 as a small producer of amateur radio equipment. The name "Zenith" came from ZN'th, a contraction of its founders' ham radio call sign, 9ZN. They were joined in 1921 by Eugene F. McDonald, and Zenith Radio Company was formally incorporated in 1923. The fledgling company soon became known for its high-quality radios and electronic innovations. Zenith introduced the first portable radio in 1924, the first mass-produced AC radio in 1926,[4] and push-button tuning in 1927. It added automobile radios in the 1930s with its Model 460, promoting the fact that it needed no separate generator or battery, selling at US$59.95. The first Zenith television set appeared in 1939, with its first commercial sets sold to the public in 1948. The company is credited with having invented such things as the wireless remote control and FM multiplex stereo. In fact, Zenith established one of the very first FM stations in the country in 1940 (Chicago's WWZR, later called WEFM, named for Zenith executive Eugene F. McDonald), which was among the earliest FM multiplex stereo stations, first broadcasting in stereo in June 1961. The station was sold in the early 1970s and is now WUSN.