Complex sentence: Señal Colombia--a state-owned channel--first made digital terrestrial television broadcast tests in 2006, in northwest Bogotá and downtown Cartagena, transmitting in the three DTV formats (ATSC, DVB-T, and ISDB-T).
Split into simpler sentences: Señal Colombia--a state-owned channel--first made digital terrestrial television broadcast tests in 2006, in northwest Bogotá and downtown Cartagena. Transmissions were made in the three DTV formats (ATSC, DVB-T, and ISDB-T).