stubby

I recently picked up an RH-10 and notice now that it does not have a settable shut-off timer. I was hoping to be able to set the unit to play for an hour at bedtime and then shut itself off. If anyone has any info on this or a workaround it would be appreciated. I record a five hour radio show that I don't bother to slice up into tracks, I just play it back as one long mp3. I thought it would be nice to start each night at the 2nd,3rd,4th etc hour by use of the timer. If not oh well, I'll just have to start making individual files and and set the playback mode. Thanx for any help