On hundreds of stations in America there is a second channel or even third channel you could listen to. No one is listening, but that doesn't mean it's not there. Only consumers with a HD capable radio can tune into this HD-2 channel and very few of them do. Conceptually it's a leap for consumers to understand that each frequency can carry more than one channel of programming. HD radios have generally failed to convey this in an easily understood interface. None-the-less, these stations are still there. Most of these stations are running original content, but increasingly on the HD-2 and HD-3 sub channels I am seeing simulcasts of other stations. Allow me to give a few examples.
98.1 KUDL in Kansas City is simulcasting 980 KMBZ-AM,on their HD-3 another Entercom stick. This approach makes a lot of sense as AM radio dies a writhing static and bleeding noise filled death. On their HD-2 is 1660 KXTR-AM, a classical station.
In Los Angeles 95.1 KFRG is simulcast on the HD-2 channel of 94.7 KTWV. Interestingly enough, Mt. Wilson FM Broadcasters owners of 105.1 KKGO asked the FCC to rule on that Viacom’s arrangement. the suggest that these simulcasts violate the FCC’s multiple ownership rules. I doubt very much this is a total simulcast, its probably a goulash of WFAN programming with local ads inserted.
In an interesting variation 660 WFAN-AM in New York is simulcast on the HD channels of three stations in Florida. In Orlando, HD-3 on 105.9 WOCL HD-3, in Tampa,on the HD-3 of 94.1 WLLD HD3 (94.1) in Tampa and in West Palm Beach the HD-3 channel of 104.3 WEAT. More here.
Most recently daytimer 820 WSWI-AM the University of Southern Indiana’s college station has begun simulcasting on the HD-2 channel 90.7 WPSR a 14,000 watt high school station. More here. I'll note now that this is the first case of a college station simulcasting on an HD channel at another station.