Old Radios are not worth the trouble. For a few bucks over the replacement batterys in an ancient 4 channel you can have a good 6-7 channel computer radio with Rx and servos, plus multi plane memory. Trust me, if you continue the sport the old radio would be the first to go, why go there in the first place? They have very little re-sale value if any....I have about ten in the "Bone Pile".