I've tried to search, but couldn't find anything definitive. For our car, is the roof mount antenna also the AM antenna? I've been using the JDM short antenna, and AM reception has been horrible. Today, I can't even get one station. Does anyone know definitively? I know I only plugged one antenna into the back of my kenwood DNX7100. Is there a 2nd wire I have to plug into it for AM? Thanks.