transponder for redistribution to cable and satellite subscribers. United Video stepped in to assert uplink responsibilities as SSS had become embroiled in a transponder lease dispute with RCA American Communications in pertinence to a lawsuit involving RCA American and SSS's Satellite Communication Systems joint venture over the use of Satcom Transponder 18. While TBS partnered with a satellite carrier to relay the WTBS Atlanta signal to a national audience, United Video used the legally structured loophole in the Copyright Act's compulsory license statute to uplink the signal of WGN without the prior consent of owner WGN Continental Broadcasting Company (later known as Tribune Broadcasting), a model that would be used for other superstations that emerged in the coming years. United Video did not compensate WGN directly for the retransmission of its signal, though the station and its parent company received royalty payments from cable systems that received the United Video-fed signal for any copyrighted programming (local newscasts, public affairs shows, locally originated children's programs and sports) that WGN owned and/or produced. The station quickly turned into a major commodity among cable systems because of WGN's telecasts of Chicago Cubs and Chicago White Sox baseball, DePaul Blue Demons college basketball, and Chicago Bulls basketball games and its locally popular in-house children's programs like The Bozo Show (the Chicago iteration of the Bozo the Clown television franchise). As the first superstation that offered long-form newscasts (compared to the newsbriefs offered by WTCG/WTBS for most of the time until 1996 as well as an abbreviated daily satirical newscast, 17 Update Early in the Morning, which aired from 1976 to 1979 and mixed improvisational and scripted comedy with actual news content), upon moving its late evening newscast to 9:00 p.m. Central Time in March 1980, it also provided a prime time news alternative for viewers wanting to find out national and international headlines without having to wait for post-prime-time newscasts on local network stations, something of particular benefit to snowbirds and other Chicago residents who temporarily or permanently relocated elsewhere in the United States. Immediately after achieving superstation status, WGN-TV became available to an estimated approximately 200 cable systems and 1.5 million subscribers throughout the country; its distribution was heavily concentrated in the Central U.S. until the early 1980s and, by the end of the decade, had gradually expanded to encompass most of the nation with some gaps in the Northeastern U.S. that remained