I was up by Boyne Highlands back in the mid 1980s and couldn't hear anything except groundwave. Not even WWL or Central America or the Caribbean. I could actually hear groundwave from WTAC 600 from Flint, now WSNL, that night, before WCHT was using it's PSSA with 134 watts. No Radio Moscow on 600 either. Also got quite a few that same year from 40 miles away in SE Michigan at night that were usually buried in interference. Of course, the Class IVs/Class C's were all there nearly alone, except where two groundwaves were present on one channel, like WQBH and WSAM.