Ace makes a little box that you wire in line with your charger called an ADD-A-TRICKLE. You use the stock wall charger and the Ace unit automaticly switches it to trickle. Then you just leave it plugged in for ever.

I have all my planes on trickle, all the time. Because all of my planes are always ready to fly, I walk in and pick the plane that suits my mood at that moment.

I've been using the Ace ADD-A-TRICKLEs for about 15 years now. I haven't had any problems. I love them. I prefer the manual units. The new units are automatic. Red LED's indicate trickle or regular charge rate.