Recently I bought a Hobbico ESV to check my Rx batteries.I've always just charged overnight and flown. But it was on sale and, well you know how it is. Anyways, after flying for about an hour and a half I decided to take a read out of the Rx battery. I really haven't managed to grasp this whole electrical thing but I got a red light/charge light and a reading of 4.78 on a typical 4.8 battery pack. Does this mean I was near serious trouble had I kept flying? How low a read out can one get and still be reasonably safe? Hope this question makes sense as I know there are a lot of factors invloved.