Oh boy, don't get me started. Every now and then someone will hear an old CBS broadcast identifying from New York and ask, "What's with this WABC?" Well sonny...there wasn't yet any ABC, for one thing, and for two things, CBS had a subsidiary,
Atlantic
Broadcasting
Co., that existed to own their O&O stations. Thus WABC - and their TV station, which prior to going commercial was W2XAB. The call sign WCBS became theirs in 1946 when a station in Springfield, IL, agreed to let it go.
Some calls stick around long after the owners. KRNT, Des Moines, began in 1935 under the
Register '
N Tribune

papers. The Trib went the way of all afternoon dailies in the '80s, the Register got out of the broadcasting game, but KRNT it remains. Similarly, WMT of the Waterloo (IA) Morning Tribune stayed WMT even after moving to Cedar Rapids.
Sometimes the calls are hard to figure out. My dad and granddad both worked for KGLO in Mason City, IA, owned by the
Globe-Gazette paper. I never knew what the call sign meant till just recently.
My favorite story was that of WEAF, the AT&T station that later become one of two NBC flagships. It got its name from the four elements:
Water+
Earth+
Air+
Fire.