Announcers who read portions of plays, poems, or novels on the air are considered to be putting on a performance. As with any performance of copyrighted material, permission must first be obtained to put on the performance, otherwise the announcer is guilty of copyright infringement. Copyright infringement can also occur when an announcer rebroadcasts another station's signal (by playing a recording of it) or broadcasts a syndicated radio show without permission, or, at a time other than the agreed one. Other offenses include rebroadcasting sound recorded from copyrighted television shows or movies, over 30 seconds in length. Bootleg recordings of bands also may not be played without the written permission of the band. You may assume it's okay to play any material KPSU places in its library. A good rule of thumb as far as appropriate content is whether the source material was originally commercially available.