Digital servo's will not fix the problem. You need to get a match box or a radio that will allow you to mix 2 channels together to operate as one. I am not familar with JR radio's, however with a Futaba 9C, you program the elevator as the master channel and then program one of the other channels as a slave. Doing this will allow both servos to operate as one and the trim will adjust both servo's. Good Luck, Dave