Boston radio dial in 1963
Sun Nov 24 19:43:41 EST 2013
"WRKO tweaked the daytime signal again around 1970 where with a good car radio you could get a signal on the Mass Pike as far as the NY state line."
It was at about that time that daytime protections on "clear" channels were reduced to (I believe) 1000 miles, which allowed lots of AM's to let out their daytime patterns a bit and/or increase their daytime power.
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