I've been doing a show (started out that way, now moved to 2 shows) at my university radio station this past year. It has been a great, GREAT learning experience for me, because it litterally forces you to learn how to take care of all aspects of DJing.

When I first started I thought I could get my doing this all with free music, i.e promotions, free tracks, ect ect...but the fact of the matter remains, that not matter what, your going to have to spend some money on this.

My uni gets its content as well, through labels and such, but NOTHING, i mean NOTHING to do with EDM. Thats that, get ready to pay

I've found that many TA's in the producer forum LOVE airplay, just be sure to ask, as common courtesey...after all, they DID slave away at a track for months, they probably would like to hear it in a mix of some sort.

As far as callins, ect, thats all dependant on how you decide to produce your show. Do you wanna mix live, does your station even have TT's/CD's and a mixer for them?
I started out doing hard cuts of tracks, and realized it sounded like shit, so I bought Ableton and got into that, making a new mix every week. With ableton you could easily integrate interviews, ect ect...it all just depends on how much time your willing to spend on this new hobby.

ANYWAY, best of luck, and if you ever need any help, PM me.

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"I believe in a long, prolonged, derrangement of the senses to attain the unknown" - Jim Morrison