Froggy 101 is the #1 rated country-western station in Scranton, Pennsylvania.
Dwight Schrute has a sticker advertising this station on his desk.
In Season 4, Ep 4: Money, a sticker is seen when Michael is called by his boss to have a discussion at the telemarketing job.
In Season 6, Ep 22: Secretary's Day, the Froggy 101 sticker is seen on the wall between Kelly 'Erin' Hannon and accounting.
In Season 7, Ep 17: Threat Level Midnight, there is a sticker on the advertisement board in the bar where Michael and Andy are talking.
In Season 7, Ep 18: Todd Packer, Jim suggests playing a prank on Todd Packer that includes Froggy 101.
In Season 8, Ep 2: The Incentive, in the Tattoo Parlor, there is another sticker.
In Season 8, Ep 3: Lotto, there is a sticker visible on the mast of the forklift in the warehouse.