WDEF-TV is the call sign for the CBS affiliate in the Chattanooga, Tennessee market. It broadcasts on digital channel 12. Its analog 12 was shut off on February 17, 2009. WDEF's subcarrier, 12.2 is high definition.
WDEF has primarily been a CBS affiliate since its inception. It had secondary with DuMont (until it went dark in 1955), NBC (sharing with WROM/channel 9 to 1956, when WRGP/channel 3 signed on--now WRCB) and ABC (to 1958, when WROM moved to Chattanooga and changed its call to WTVC, the current ABC affiliate). They picked up secondary affiliation with UPN in 2004. It ended in 2006 after UPN and the WB (then on WFLI/channel 53) shut down and merged into the CW.
WDEF's digital signal went on the air in 1999 on channel 47. Upon switching off its analog signal, it moved to its post-shutoff selection, channel 12.
|12.1||12.1||WDEF-DT||Main WDEF (CBS)|
Current CBS Prime-Time Schedule
|Monday||Prime News at 7||The Andy Griffith Show||Kevin Can Wait||Man with a Plan||Superior Donuts||The Big Bang Theory||Elementary||News 12 Nightside|
|Tuesday||Prime News at 7||The Andy Griffith Show||NCIS||Bull||NCIS: New Orleans||News 12 Nightside|
|Wednesday||Prime News at 7||The Andy Griffith Show||Survivor||SEAL Team||Criminal Minds||News 12 Nightside|
|Thursday||Prime News at 7||The Andy Griffith Show||The Big Bang Theory||Young Sheldon||Mom||Life in Pieces||S.W.A.T.||News 12 Nightside|
|Friday||Prime News at 7||The Andy Griffith Show||MacGyver||Hawaii Five-0||Blue Bloods||News 12 Nightside|
|Saturday||Paid programming||Ransom||Crimetime Saturday||48 Hours||News 12 Nightside|
|Sunday||60 Minutes||Instinct (2018)||NCIS: Los Angeles||Madam Secretary||News 12 Nightside|