One of my TM Twins pooped out yesterday - no VFD display, no response to remote, but would boot and tuner worked - but no control from remote or box buttons.
Quick investigation showed that the 100uF 400v electrolytic smoothing capacitor had overheated and blown, with signs of overheating around the ViPer22A SMPS management chip.
Dug around in my gear and found a 100uF 400v on an old PSU board from something or other. Replaced the frazzled capacitor and hey! presto! Everything working again.
If you haven't got the components, a quick check on eBay will find both the chip and the capacitor for a couple of quid, so don't automatically pay for a new PSU from Technomate if this happens to you!