The radio program is public domain because it's on a non-profit station. There is no need for liscening agreements when one tapes a radio program while it is broadcast to the general public.

You can get away with taping a radio program for your own private use. No one is going to get in a tizzy about that. However, a radio program itself, and the content therein, are not in the public domain, whether or not it is a non-profit radio station. What you cannot legally do without all of the requisite permissions is distribute that recording.

Non-profit radio stations, be they community, public, college, etc. pay to license the music (and sometimes other content) which they broadcast.