Emilio Nicolas Sr., who built a struggling Texas television station into the company that became the Spanish-language broadcasting juggernaut Univision, died on October 12 2019 at his home in San Antonio. He was 88. His son Guillermo said the cause was complications of progressive supranuclear palsy, a brain disorder. In 1955, Mr. Nicolas started working at KCOR, a Spanish-language television station in San Antonio owned by his father-in-law, Raoul Cortez. KCOR struggled initially, and Mr. Nicolas did all he could to make it succeed. In 1961 Mr. Nicolas bought it with four other investors and renamed it KWEX. Spanish-speaking audiences were receptive, but advertisers remained elusive, at least in part because KWEX was an Ultra High Frequency, or UHF, channel. Mr. Nicolas and Rene Anselmo, one of his partners, went to Washington to lobby Congress in support of the All-Channel Receiver Act, which would allow the Federal Communications Commission to require that new televisions include UHF tuners. The act became law in 1962, opening the way for Mr. Nicolas and his colleagues to expand. The company soon became two connected entities: the Spanish International Communications Corporation, which acquired stations and affiliates in Los Angeles, New York and other major markets; and the Spanish International Network, which provided programming and arranged advertising for those stations. In the 1970s, SIN became one of the first networks in the United States to deliver its programming via satellite. Hallmark bought it in 1987 for more than $300 million, a sale prompted by internal disputes and an F.C.C. ruling that too much of the company was owned by foreign investors. It adopted the name Univision shortly after the sale. Univision — best known for telenovelas and the variety show “Sábado Gigante,” which ended its long run in 2015 — said that it earned $2.7 billion in total revenue in 2018 and that its programming reaches more than 95 percent of the Hispanic households in the United States, a population that is now approaching 60 million. He and Emilio Azcárraga Milmo, the son of Emilio Azcárraga Vidaurreta, a former partner, teamed up to build Galavisión, then a cable channel, into another Spanish-language broadcasting group. The company came to be called Nicolas Communications Corporation and was successful enough that in 2003 Mr. Nicolas was able to sell it to three different companies — including Univision. Emilio Rafael Nicolas was born on Oct. 27, 1930, in Nueva Rosita, a small town in the state of Coahuila, about 50 miles from the border with Texas. After graduating from high school, he moved to San Antonio to attend St. Mary’s University, where he studied chemistry, biology and mathematics, graduating in 1951. He earned a master’s degree from Trinity University in San Antonio in 1952. he went to work at the Southwest Research Institute in San Antonio, where he studied arteriosclerosis and the polio vaccine. He worked there for years before taking a job at KCOR. In 1953 he married Irma Cortez, whom he had met at St. Mary’s. In addition to his wife and his son Guillermo, he is survived by another son, Emilio Jr.; a daughter, Miriam Relyea; five grandchildren; and seven great-grandchildren.