My favorite call is a Lohman "Circe" 3-in-1 predator call. It is a mouth call that will do a jackrabbit, cottontail, and coaxer. I have a variety of calls, but I usually have my best luck with this one. I usually start with one of the two rabbit calls, giving it about three to five brief blows, and then wait about five to ten minutes before doing it again. If there are any coyotes around, they will usually respond within ten minutes, but occaisioinally they are slower.