Hello, having recently acquired this as broken/for spares, does anybody have access to a repair manual? Found lots of them for the 350 GSM model, which is the DC TIG/MIG version. Am suspecting one or more of the mosfets have gone, machine on stick puts out 50-ish volts until you try to strike an arc, then the output collapses to 0 volts. Service manual would probably show how and where to measure, so looking for one. Thanks anybody.