>Anyone have a 13-volt ARC-4 dynomotor to swap for a 26-volt one? You're looking for a DY-10/ARC-4X dual input voltage unit. They aren't as common as the DY-9/ARC-1, but still they aren't terribly hard to find either. Are you putting an AN/ARC-4 on the air? The receiver section doesn't have an RF stage, so they aren't real sensitive! Mike / KK5F