Fixed!!! 😊 Found two bad filtering caps in the PSU section of this high-grade PPM from @questiondeson. Actually not shorted but leaky enough to make the corresponding rectifying diodes drop their output voltages substantially... preventing all major supply rails to work at their nominal values! Now the input voltages to the regulators show the expected +&-20V :-) Replaced the old 25V-rated caps with 50V, high-grade, Nichicon's PW series. With such a limited headroom, no wonder the original ones didn't survive a probable high voltage surge... #RTW #PPM1206D #RTWPPM1206D #HighEndPPM #PeakProgramMeter #StandAlonePPM #VintagePeakMeter #ProfessionalPPM #ProfessionalPeakMeter #Repair #QuestionDeSonStudios #StudiosQuestionDeSon #StudiosQuestionDeSonParis #StudiosQDS #QDSParis #StudioPiscineATokyo #TheGoodDoctorPrager