Bob, I tend to use the Plain Yelp and add my own emotion to it. As a Compation caller I tend to practice Stage talk in the yelp as I work birds, not sure if it works , but some birds fall for it

huntnma
the Assembly Yelp is a long series of yelps with an excited faster yelping emotion. This call can have up to 12-15 yelps in the call, also a good call that will work in spring aswell as the fall...BT