I tell ya RoundMan I live right down the road from you a ways in charleston, And I hunted for over a year to get my first Bobcat, although I seen a few while calling( very few), I did get one. And I had a great time doing it and I learn alot. Yotes on the other hand is a little more tricky than hunting cats, On them you have to pay a little more attention to the wind,since sometimes they cicle down wind to check things out first before they come in the the call.
What type of calls are you using? I use both a E-caller and mouth calls, but I have had better luck with mouth calls on both yotes and cats than E-callers. With a E-caller and yotes I tend to overcall a little.
I usually start off with a series of howls and then wait for about a minute, Then start my distress calls and I make then last only for about a 10-15 seconds then I wait for about a minute, then if repeat the distress call then wait for about a minute, If nothing have coming in by then I raise the volume of my calling a little on the next series of calls and wait for about 2-3 minutes and I do that a couple of time then I go back to the lower volume calling for the rest of the set-up. And i usually stay there for about 20-30 minutes when I'm hunting for yotes.
I am not a coyotes expert, But I have taken a few over the years. My main target for the past several years has been Bobcats.
But that sequence has called in cats, yotes and even foxes for me. So thats what I use every time I call. Except for the Howls on the cats and foxes