I've given up on the crow and owl call as I have never gotten a response from either of them, at least in my area. I now have both a jake gobbler and a coyote howler. It sounds like the coyote is a good call for gobblers on the roost and the gobbler works well during the day (yes, be careful for other hunters).

So, if it took me 3 hours to slowly walk around an entire farm, would you call every 15 minutes or so?