I had a DMR-E85H with the same problem - it began when it was around two years old, when it would power off when completing an HD -> DVD dub. It steadily got worse, to the point where it wouldn't even power on without going through several self-test/power off cycles. I contacted Panasonic, who told me to take it to their authorised repair centre and get a repair report prepared. This came back saying it needed a new PSU (no surprises there!). However, after a bit of arm twisting - and despite the fact hat by now the machine was approaching its third birthday - Panasonic agreed to provide the new PSU free of charge, so I only paid the labour charge for fitting it. OK, so even that came to £50 + VAT, but it might be an option if you'd like a bit more use out of your recorder and don't want to risk destroying it with a botched DIY repair.