12 - KTXA (21), Fort Worth (Ind. KTXA, virtual channel 21 (UHF digital channel 18), is an independent television station licensed to Fort Worth, Texas, United States and serving the Dallas–Fort Worth Metroplex. Spectrum TV Channel Lineup in Dallas, Texas (75243). TXA 21 - KTXA Channel 21 Television. Find out how to watch MeTV in Dallas on affiliate KTXA (Over the air).