Hector,

Having the portable may just be the problem. I have had a minimum of 4 portable, counting all the "replacements" and I'm not real confident that my current one will be any more reliable than the rest.

That being said, I had the same unit hard wired in my Beaver coach and it performed flawlessly, in constant use as we are full timers, for 4 years. It was that experience that lead me to purchase the portable unit for the bus.