Alright, it is probably an input voltage low error. You can go into the menu and reduce it to minimum (10 or 10.5) , but the real trouble may be the radioshack ps is not quite big enough. Would you happen to know the wattage or current of the ps? If it's around 12-20 watts then it is too small and the only way it will work is to keep the charge current down around .8 amps or so.