Yeah, you just call in when Derringer says it's coming up next, about 5 minutes prior. It seemed like they were doing a bit of a pre-interview with me though, just to see if I'd be able to answer any of the questions so, since they said the questions were all going to be about Clapton, Beck and Pink Floyd, I told them classic rock was my forté and the guy (Flairboy I think) said he liked what he heard and I was in.
This was my first time actually getting through for Stump the Chump but I get through a lot on the other shows since my speed dial at work is so quick.