NEW YORK — Barry Diller, who started the FOX Television network for media magnate Rupert Murdoch, said Aug. 25 that he had reached a deal that will give him control of the nation's sixth-largest TV-station company, Silver King Communications. Under the deal, Diller will buy 20 percent of the company for $22.625 per share and also receive an option for control of another 70 percent of the company's common stock. Silver King owns 12 television stations, reaching 28 million homes, and could form the backbone of a new television network - a longstanding ambition for Mr. Diller. His Arrows Holdings company said Silver King serves eight of the 12 largest television markets in the United States, including New York, Los Angeles, Chicago, Philadelphia, Boston, Dallas, Houston, and Cleveland. Murdoch started FOX Television in the mid-1980s in a similar way, buying its core stations from Metromedia in a multibillion-dollar deal and then expanding. Diller will file with the Federal Communications Commission for a change of control at Silver King and will take control of the company once that change is approved and the stock option is exercised.