Update, I took unit into Maplin where I had purchased it about 2 years ago, told them I wanted some info on the factory re-set procedure if possible, they said it might not be getting enough current to start up properly, he produced a digital meter and proceeded to measure the DC voltage, Ohms law must not be one of the subjects for Maplin employee's, I just did not have the heart to tell him I had already tested it on my Workshop Thurlby/Thandar PSU and had eliminated lack of voltage or insufficient current as the problem, I am trying to get a schematic from the manufactures, but no luck so far in locating them. I had a spare unit of different manufacture pressed into service so down time is not a problem.
