Hillbilly.

Elkcrazy8 explained it pretty well. I'm really surprized that someone don't have a better call and some video's out there. When antelope go in the rut they get dumb real dumb. Between calling(call like a buck) and a decoy that dominant male will come from a long ways away to chase off a smaller buck. You can move your decoy head towards the buck to an aggresive posture to get the buck worked up and switch it so the back in is pointed towards him for a cowardly posture. Usually the cowardly posture will finish bringing him in. I did not get to use call or decoy this year. I shot my antelope before the rut began.

I've personally thought about trying to make and easier to use antelope call than the rubber band ones out there. A challenge call to me sounds like tizzzzzzzzzeww pit pit. The little ending sounds is really neat in it's own way.

Good luck in the future and I'd go out during rut and listen to a few bucks calling and store it in the memory bank then you willl know that one and only sound.