My name is Bill and I live in Palm Beach County. I have been an electronic tinkerer since age 5. Recently an elaborate system of mine broke down and the person who sold it to me changed from one company to another. His new company does not service the system that I bought from his old company and his old company no longer serves elan either. This left me having no local contact except to call on people 40-60 miles away. Thus I took it upon myself to use my medical skills to fix my system. If my preamp was a person I would have been sued a long time ago. My journey to simply find out why my keypads will not control my preamp led me into strange areas like "punchboard repair" , RS485 circuits, optoisolators, use of toners and probes, as well ascircuit board repair. While my elan z630 is still ailing from a bad ir port.....I must admit I am having fun. My enthusiam for electronics is there. I know my limitations. I am very appreciative that the members of this site embrace new people like myself and enjoy sharing their knowledge.