using the charge socket you're stuck with standard, dumb slow tx chargers. There is circuitry within the GT3b that prevents proper peak detecting chargers from working.
one person put a 2 pin receiver battery type plug on some short leads on the battery box inside the radio. Open the battery door, plug it into any multicharger like the accucel 6 types, set charging settings and away you go.
The best, although by far the most expensive way, is to get a Maha charger, preferably an 8 cell one. Then remove the batteries every time you charge. Maha C800-S will cost you about $75 but is the optimum charger for the cells. It peaks each cell individually so ensures the balance of the cells and means no cell will be overcharged - which can happen as cells do slightly go out of balance when in a pack.
I've got battery holders i use on the multicharger i use to charge my model's batteries just like Racer X8000 says.. does the job, its basically the same as putting a connector on the radio's battery tray. It isn't 100% ideal for the batteries - it will shorten their life somewhat compared to the maha.. but $75 buys a lot of ready to use (lsd) AA nimhs.
Last edited by skree; 09-11-2011 at 08:49 PM.