I went out deer hunting the other day, just to kill a Saturday & was walking to my stand.  I heard some hens cackling & cutting up down in a holler West of where I was walking & decided to try something.  I sat down, threw my orange vest & cap in the bushes, & proceeded to "yelp" to  the hens with nothing but my my voice.  Twenty minutes later, I had a hen at 12 steps.  I hope I can do this to a gobbler come next Spring.