My long-faithful 1715 suddenly (well, after a hurricane) lost heading and bearing pulse. The display seems fine, but nothing from up the mast. I brought the antenna down, and found some degree of burned smell and some water inside the case. I have not yet found any voltage at the antenna, and test menu gives me "NG(0)". What tests can I run to determine whether the antenna 1. is not getting power, although the cable appears undamaged, or 2. is toast?