Everyone else has covered it fairly well but il add my 2 cents.
My approach is a lot like lonehowls. I like getting my coyotes close to me so even when running an e call it's not more than 30 yards away.
As for using hand calls as a stand alone I do probably half or more of my coyote stands with the e call still in the truck.
Have a good position to sit and don't make sudden movements and the coyotes will often look right at me but keep coming as they can't place what I am sitting against a bush or snowdrift.
I use hand calls at all times of the year and have success at all times as well.
