Have you tried an attractant along with the call? A friend of mine has use one from Cabela's and likes it http://www.cabelas.com/cabelas/en/templates/product/standard-item.jsp?_DARGS=/cabelas/en/common/catalog/item-link.jsp_A&_DAV=MainCatcat20712-cat20835_TGP&id=0041317228308a&navCount=2&podId=0041317&parentId=cat20835&masterpathid=&navAction=push&catalogCode=UK&rid=&parentType=index&indexId=cat601233&hasJS=true

But if it was me if they only got within 200 yards and I had a clean shot then I would take it and not worry about him getting any closer.

I agree with Critter, I'd be taking that 200 yard shot. Heck, I'll take a 300 yard shot if circumstances allow, ie solid rest and animal not moving. Does your state limit caliber usage? Because if you're only allowed a 22 mag or shotgun, I understand the need to get em closer.

I hunt coyotes year round in NE Wisconsin. I started hunting coyotes in Colorado when I was stationed in Colorado Springs. We owned a small ranch on the eastern plains that was a favorite playground for lots and lots of coyotes. I initially hunted them during the day but soon found I had better luck in the dark. I sometimes ambushed them from the deck on the back of our house. I hunted over the best bait pile in the area...my wife's chicken coop. Since we lived in the wide open spaces bullet travel on a miss wasn't too much of a concern since my nearest neighbor was about 3 miles away.
That all changed when I moved back east. The hunting lanes are very restrictive, there's lots of cover and you'd better know where that bullet is going. I still hunt primarily at night using nite optics from ATN and an illuminated 3-9X42scope for dusk and dawn. Most of my kills are between 0200 and 0530...I'm not sure why. I use a Ruger mini-14 with 55gr .223 screamers that move fast but don't damage the pelt too much. I always survey my shooting lanes in the daylight, ranging any occupied bldgs and logging them into my maps. I also use a Garmin cx60 with topo so I know where roads, rr tracks and waterways are when I map a clients property before the actual shooting starts. I also make sure the client contacts local law enforcement and let them know what I'm doing. It's a lot of work and things I never had to do out west. It's all necessary not just because of liability but more importantly to prevent accidents. I even take these steps when I hunt them on public land near my home...just a good habit.
I can tell you that a 200yd shot on a target that small here in WI is probably extreme. I'm used to daytime shots at or beyond 300yd shots out west but probably wouldn't do that here unless I was absolutely sure of my backdrop. I would suggest you try to bring them in closer than try a shot you're not sure you are comfortable with. It just isn't safe and lawyers are very expensive. Once you make that shot you can't take that bullet back. Talk to other predator hunters in your area and see how they bring them in close. Just because something is sold at Cabelas or someone uses it on the Outdoor Channel doesn't mean it works. Talk to the old timers, especially trappers since they practically live out there. It can save you a lot of time, money and grief. Most of my shots are within 100yds during the day and definitely under that distance in low light...my optics are only good to 100 meters at night
Best time to hunt them? The dead of night in February. The females are in heat and like most males the boys just totally lose all common sense when they're chasing the girls. Best place I've ever found to hunt them besides next to the chicken coop? Along a trapline. Just don't hunt too close and respect the trapper's line. Hope this helped and good luck huntin the dogs. They are a wily opponent and will try your patience but you can prevail.

Never Bring a knife to a gun fight