Asterix for a radio phone queue?

This is actually for a podcast, but it’s a radio style set up.
This is almost like a conference call setup. People will dial in, and everyone can hear. But I need a way to switch between callers (only one can talk at a time).

Can I do this with an Asterisk setup?

I do not believe that this exists for asterisk. If you post a bounty on voip-info.org and email the dev list (lists.digium.com) then you should find some one that can help you with it.