I guess I just made another SP1200 user happy! ☺️. . This time by replacing the original but dead +5V supply's (15 amps!) diode brigde. Actually, only one of the four diodes in it had gone open (wasn't conducting at all), but that was enough to bring the +5V rail down to 3V or something, and with an awful ripple you just couldn't even picture... so, no wonder it wouldn't try to boot the software from the diskette drive... because with a supply that low, the drive couldn't even start to spin!!! . Now this puppy is back to work after having tested all functions and both RAM sections, let's just do some light SP1200 housekeeping (that is, cleaning all keyswitches, drum pads and sliders 😉) . #Emu #EmuInc #SP1200 #EmuSP1200 #VintageSamplingPercussionSystem #VintageDrumMachine #DigitalDrumMachine #Repair #StudioPiscineATokyo #PiscineATokyo #TheGoodDoctorPrager