If an AM station adds an FM simulcast that doesn't cover the entire market (as 105.5 doesn't), they often keep the AM station broadcasting the same programming as well, to fill in the holes in the coverage .
I doubt they'd just turn the AM station off. Even with AM's sagging listenership, you still can do something with a decent AM signal in a large market like Denver. Maybe it would be brokered ethnic programming, maybe it would be sold to a non-profit broadcaster. Several Catholic groups have lately been buying AM stations in large markets to air their programming, be it EWTN, Sacred Heart or one of the others. One Catholic group just bought TWO AM stations in the Dallas market, one for its English-language programming, one for Spanish.
Gregg
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