I use the siren when I have a stand that nothing came in, but I see lots of coyote sign in the area.
I'll run the siren a couple of times, then listen to pinpoint the location, then move my next stand to that area.
I've called multiple coyotes using that technique. /ubbthreads/images/graemlins/grinning-smiley-006.gif
If I feel like I need to stir things up a bit on a slow day, I'll use the "Coyote Locator" howls to get them up & paying attention, then start my stand.
You'd be surprised how much better "alert" coyotes come into the stand, vs when you are calling & they are slow, or layed up sleeping already. /ubbthreads/images/graemlins/grinning-smiley-003.gif
Barry