Here's what I use on my roasts for smoking.
3/4 c salt, 3/4 c brown sugar, 1 T onion powder, 1 T garlic powder, 1/2 t turmeric, 1/2 t cumin, 1 t black pepper, and 1 t ground thyme
I have a note below my recipe that says add worcestershire sauce and balsamic vinegar and a bit of water to make it into more of a marinade for jerky. It has been a while since I made jerky with thisw and don't remember the details of this addition. Of course if you like hotter jerky, add hot sauce.