From  the Annals of TV Pioneers –  Dallas TV station KRLD (now KDFW) first signed on the air on December 3, 1949.  KRLD was a CBS affiliate started by the since closed Dallas Times Herald Newspaper which also owned KRLD AM radio. The new TV station used the call letters of tis radio sister which originated from the radio station’s original owner, Radio Laboratories of Dallas. Channel 4 was the third television station in the Metroplex.  KBTV (channel 8, now WFAA in Dallas) aired in September of 1949; and WBAP-TV (channel 5, now KXAS in Fort Worth) had been broadcasting since September of 1948. KRLD’s studio was located in the Times Herald offices at 1101 Patterson Street.

Photo of KRLD’s transmitter being lifted to the top of its first transmission tower at Griffin and San Jacinto.  From http://www.akdart.com