I bought one of those bullhorn/siren combo's back in 2006, when I joined PPHA. It's gathering dust along with a bunch of gadgets and widgets I thought were good ideas at the time. I have only once heard a coyote in my area howl to a siren. I was sitting in a location sandwiched between 2 country developments, when I heard an emergency vehicle going down a state road siren blaring. My ears went up, I heard several dogs in the area open up but no coyote. Then the fridge light in my head went on ( only took 9yrs) and I found a female coyote howl on my Wildfire and played it 1 time full volume, along with the dogs. Whoa! I got an immediate coyote response right down the hollow I was in about a 1/4 mile and a few extra dogs...and no I didn't get that coyote ..but I made him,her,or it play the game so that counts in my book...I don't care what Hern's rules are....lol..if you want that bullhorn thing PM me your address and I will send it to you "Free"...if it doesn't work for you on coyotes,you can call the kids with it or the wife...a word of caution I tried the wife thing, that's why it's gathering dust.