While driving around the eastern edge of the Grand Canyon north of Tuba City, Arizona, we passed through what I believe was the Out Reservation. We turned on the radio to discover that there was only one station broadcasting. According to YouTube user jbegaye2001, the station is KTNN AM 660, “The Voice of the Navajo Nation”. It can be heard all over the Four Corners region. He claims that almost all of the programs are done in Navajo including sporting events.