Instrumental Hip hop radio?

So, me and my friends really like to cipher or freestyle or w/e you want to call it. The problem is, it's hard to find instrumental beats with no vocals that play continuously. The deal is that if one of us is rapping and is on a roll and the beat stops (cuz the youtube vid is usually over) then it's no fun and we have to start all over. I was wondering if there's a radio station that provides ONLY instrumental hiphop beats.