I recently received a new JR 9 channel rx that would not bind with my 9503 tx. After trying everything I could, I finally attempted the binding process with a different rx battery. I had been using a well charged 5 cell pack. When I replaced it with a 4 cell pack, it binded with no problems. I called Horizon and discussed the issue with their tech reps. They say they haven't heard of this before, but trust me, it happened. The new radio works flawlessly and on the 5 cell pack. Just won't bind....