A BBC Micro power supply that released its magic blue smoke. I replace the failed Rifa X2 caps and service the whole PSU with the Retro Clinic advanced kit.
An Atari Lynx II that won’t power on, fixed by replacing the power stage components (Q12, D13, Q7, Q8, R74) and recapping the board with a Digital Delights kit.
A 3DO FZ-1 bought as working had an intermittent fault. Leaking power stage capacitors were the cause, and replacing them exposed a failed regulator and blown fuse.
A dead Spectrum +2A/B power supply, a dangerous old mains plug and the fuse that is nearly always the culprit, plus the hidden second fuse you should check.
A Samsung 40 inch LCD TV that just clicks and never turns on, fixed by spotting and replacing two worn 1000uF 25V capacitors on the power board, with ESR meter results.