No coyote will ever come in from downwind if they smell you and they will wind you more than 200 yards away.
If volume is an issue, do the cheapest thing and get a quality mouth call. They are louder than hell and relatively cheap.
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The guy above is from MI and makes his own calls commercially. I can recommend them. Generally, you should set up with a cross wind. Coyotes are predators and they know it is stupid to approach anything in a downwind direction. If you have a cross wind it is virtually ideal. If the wind is in your face, they are going to try circle around to your back to approach from that direction and you might never see them before they wind you.