No Subject

I think it is accurate to say that the comfortable listening range of all
FM stations back then tended to be significantly greater, even with the
receivers of the day, because of another factor particularly (other than
the uncongested spectrum): monophonic transmission.  The cost of
transmitting in FM stereo is very high.  Per the usually-quoted figure,
there is as much as a 23 decibel penalty in signal-to-noise ratio for
stereo operation.  Effectively that shortens the range by quite a lot. 
Another cost of stereo is worsened multipath, but that's a different
discussion.
 

------------------------------