Bob began his broadcasting career co-anchoring “AgDay,” a nationally syndicated farm news report. When sports network ESPN debuted in 1979, Jenkins was hired to cover racing, with a specific focus on NASCAR, but soon branched out to cover other forms of motorsport for both ESPN and ABC. For most of his tenure at ESPN, Bob was the host of SpeedWeek, a news show dedicate entirely to racing in all its forms.
From 1979 to 1998, Bob was also a familiar voice on the IMS Radio Network, and when the Brickyard 400 NASCAR race made its debut at the Indianapolis Motor Speedway in 1994, Bob acted as the point man for television coverage. He remained active with ABC and ESPN through the 2003 season, and later served in a variety of roles with the Speedway itself before returning to television broadcasting with Versus and later, the NBC Sports Network (NBCSN). Bob retired from television in 2012, but continues to serve as both the voice of the IMS public address system and an emcee during key events.