I have found an Yongnuo YN685 E-TTL Speedlite Flash that says it is compatible with my current Yongnuo wireless flash trigger set. I have not used one of these before but does this mean that I can use my old flash on the wireless trigger set (just like I always have) and than use this one on another light stand without any need of getting another radio receiver? So with these wireless flashes, the recover it built in and than I just assign a Number to it on the transmitter that is on my hotshoe and make sure I pick the same on within the flash itself? Could it be that simple? And so inexpensive? I feel like I am missing something here.