This great (old) article by Ron Hewitt shows a simple circuit to capture an R/C signal. I built the circuit as-is with parts that I happened to have and the Michael and I modified it to fit recovery needs.
I attempted to build this similar circuit, but didn't have all the parts necessary. I got some variance where the transistor would be when I moved the gimble, but I wasn't able to complete the circuit to drive a MOSFET or anything. I like the 4013 circuit because it worked first time and is now my circuit.
This excellent page gave us a lot of good information about the way the receiver is communicating with the servos. I would have liked to build the circuit they use, but the local electronics store was out of both the 74HC123 and 74HC74! It isn't worth $5 in shipping to get $1.28 in parts, so I think I'll put off building this one until some other time.