Being a frugal shopper I've tried to scrimp on car chargers and leads and adapters for my ZTE Blade and more recently my Note and I've also spent time and effort ripping them apart to solder pins to try to encourage fast charging of my Note. While they can all charge a sleeping phone perfectly well, not one combination of bits and pieces has succeeded in keeping my Note charged while using CoPilot sat nav.
So finally I bit the bullet and bought the proper Samsung 1 Amp charger from Amazon. It was £10 with free delivery and has proved an instant hit, successfully topping up the charge in the phone while running the sat nav app. Why oh why did I not buy it sooner. It would have saved money and grief.
(It's now even cheaper than when I bought it, costing just £9.80 today.)
p.s. the supplied coiled lead is quite short when tightly coiled, which can be a good thing if it doesn't need to go far, but if you have a long distance to cover it might be a problem. I haven't tried stretching it to see how far it might go as I'm happy with it as is and don't want it to go all loose and floppy.
Samsung Galaxy Note