On 2017-Nov-05, at 9:14 AM, Rob Jarratt via cctalk wrote: "I then checked the primary side of the transformer and I could see a signal." You don't describe the nature of the signal, but regardless, seeing a voltage signal at some point on the primary is not a guarantee that current is flowing through the primary, current being necessary for induction and getting anything out of the secondaries. It depends on the primary side driver arrangement, (going by the H7861 schematic DEC used some funky arrangements, is the 7826 schematic available?), For example you might see a voltage signal from the high-side driver, but the low-side driver could be faulty.