For cryin out loud don't tell anyone else how much fun coyote hunting is! Call sour dogs are tough, and ones that get called and shot at and missed just keep us in coyotes! Seriously, just missing once isn't enough to educate a coyote, so give them a couple days, sneak into a different spot, and use a different call. I'm a hand caller and don't use electronics, but I do use a decoy, you might try a bunny or something like it, anything to get their attention and make them hot to trot on in.