Is that a gripple or something like it on the brace wire in the first pix? How do you like that vs. the ratchet tightners?
Treefarmer
Traditionally most people use a twitch (image attached), which is wood handle or metal and you can turn over time. I like these better (Ratchet type), Ive had AG animals beat up and ruin the traditional twitch's and loosen them up over time. With these there's no wood or anything to break. Also it's easier to turn these with a square fencing that I'm putting up because you are tightening parallel to the fencing, and not against it with a twitch that turns into the fencing. Which isn't a big deal with barbed wire, but is problematic with square, were your twitch will get caught up with the wire.
You can find these at most AG supply stores. I bought these at Tractor supply. These are the Heavy Duty style and run $5 bucks, not cheap, but worth it.
Ive attached some pictures of how they work, images are not in order.
I still need to make sure all of these posts are painted, with one strand of barb wire at the top, then cut off the excess tops making them all the same height.