#sciprophet5

[piscineatokyo]

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One hell of a restoration project... (cont') . HURRAAAAAYYYYYY!!!! 😊😊😊😊😊😊😊😊😊😊😊😊😊😊😊😊😊😊😊😊😊😊😊😊😊 . The Prophet-5 Rev1 has come back to life, again... at least has the CPU and logic sections, thanks to the addition of the "Tune Mod" board (for compatibility with the v5.2C software EPROMs)!!!! I am SO relieved... 😊😊😊👍👍👍 . Nonetheless, there are still three main things to solve before the restoration can be completed (with the alignment of the whole unit): first, only three keyswitches of the front panel do not respond; second (naturally), will all the audio synthesis section work correctly? and last but not least: does the restored keyboard work too? . So, stay tuned... if I may say 😉 . #SequentialCircuits #SequentialCircuitsInc #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager https://www.instagram.com/p/BmULKwhgUX5/?utm_source=ig_tumblr_share&igshid=7kdjtqbgoez2

[piscineatokyo]

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. . One hell of a restoration project... (cont') . EUREKA!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! . Après presque sept heures ininterrompues de travail, le voilà enfin qui sonne pour la première fois correctement, ce Prophet-5 Rev1 !!!!!!!!!!!!!! 😊😊😊😊😊😊😊😊😊😊 . Que de pannes déjà solutionnées (rien qu'aujourd'hui : encore une puce HS, une piste coupée, une autre pastille coupée également, des capas de bypass ajoutées pour éliminer des parasites sur les signaux des potards...) pour arriver à le faire ENFIN sonner !!! . Bien évidemment il reste encore beaucoup de soucis ici et là. Mais c'est déjà un TRÈS grand pas en avant, vu d'où il venait ! ☺️☺️☺️ . ------------------ . EUREKA!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! . After almost seven hours full of work, the Prophet-5 Rev1 is FINALLY SOUNDING!!!!!!!!!!!! 😊😊😊😊😊😊😊😊😊😊 . SO MUCH faults already fixed (just for today: another dead chip, one cut track here, one cut pad there, bypass caps added to eliminate parasitic pulses on the pots' signals...) to make it sound, AT LAST!!! . Of course, there are still A LOT of faults yet to be fixed, here and there. But it's already a huge step forward, because the synth is coming a LOOONG way! 😊😊😊 . #SequentialCircuits #DaveSmith #JohnBowen #SequentialCircuitsInc #SCI #DaveSmithInstruments #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager https://www.instagram.com/p/BqkRnIglx03/?utm_source=ig_tumblr_share&igshid=n35l5rhlfcw8

[piscineatokyo]

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One hell of a restoration project... (cont') . HURRAAAAAYYYYYY (again)!!!! 😊😊😊 . Finally fixed those three keyswitches that did not respond to presses because of a bad solder joint on the Molex female receptacle of the CPU board that connects to the Panel board: now they're working like a charm! 👌 . I will at last be able to go one BIG step forward: testing the sound synthesis section! 😊😊😊 . So, once more: stay tuned... if I may say 😉 . @dalgaard @johandalgaard . . #SequentialCircuits #DaveSmith #JohnBowen #SequentialCircuitsInc #SCI #DaveSmithInstruments #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager https://www.instagram.com/p/BnDmXZtAmzW/?utm_source=ig_tumblr_share&igshid=s02udpgzm0j8

[piscineatokyo]

One hell of a restoration project... (cont') . Preparating one small PCB that should make things much better... hopefully! . 😊😊😊 . #SequentialCircuits #SequentialCircuitsInc #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

One hell of a restoration project... (cont') . Keyboard restoration is now complete!!! . 😊😊😊 . #SequentialCircuits #SequentialCircuitsInc #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

One hell of a restoration project... (cont') . Fresh-new J-wires have been put into place after soldering onto the keyboard PCB. Of course, all eight bus bars have been cleaned thoroughly one by one, as well as the J-wires' plastic holders. . Next step in the keyboard restoration process will be the last one, actually: screwing back the cleaned key tops onto their respective key support 😉 . #SequentialCircuits #SequentialCircuitsInc #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

One hell of a restoration project... (cont') New labels for the newly burned v5.2C software EPROMs: looks somewhat neater with these, right? 😊 #SequentialCircuits #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

One hell of a restoration project... (cont') PCB4 ready! ;-) (board cleaned and recapped, new 60-way header installed, dead CMOS ICs replaced, and minor issues solved on the solder side of the board, like one resistor broken, another one disconnected on one end, and a the longest wire strap not connected to its expected source...) 😊 #SequentialCircuits #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

One hell of a restoration project... (cont') Brand-new 60-way HE10 PCB male header for the CPU board. This one carries the most important control signals from the processor and the front panel pots and switches to the synthesizing voices (and back, for the auto-tune function). Solder joints need to be in good shape (that is, not dry) in order to transfer the analog voltages correctly (this is especially mandatory for pitch control signals, where a change of one thenth of a volt can lead to variation of a semitone or even more in pitch...). #SequentialCircuits #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

One hell of a restoration project... (cont') Brand-new nylon spacers (three different heights according to their placement) for assembling the four main PCBs of the Prophet together, either to replace the missing ones or the ones that were broken. Screws (with isolating washers) added on the other side of the boards to tighten the spacers. Hexagonal spacers were chosen (instead of the original cylindrical ones) for ease of tightening and disassembly. Of course, newly installed spacers all have an imperial inner thread for the screws. That IS certainly one hell of a restoration project... ;-) #SequentialCircuits #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

One hell of a restoration project... (cont') A brand-new 60-way ribbon cable just built (with high quality, genuine 3M parts) for connecting PCB4 and PCB3 together, to replace the (almost) 40 years-old, brittle one 😊 #SequentialCircuits #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

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One hell of a restoration project... (cont') HURRAYYYYYYYYYYYY!!!!!!! The Prophet has ressucitated!!!!! All hail the Prophet!!!! ☺️☺️☺️😊😊😊🤗🤗🤗 (At least partially: the CPU section now works almost perfectly, except that only three keyswitches don't make it down to the processor; there's still the Tune Mod to add; and, last but certainly not least, there is yet the whole PCB4 to check out, with all its synthesis voices to verify. Anyway, finally being able to start the CPU up correctly by simulating the presence of the Tune Mod is already a HUGE step forward since the last time this Rev1 has been known working... that is, SOME years ago!!! 😉) #SequentialCircuits #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #DaveSmith #DaveSmithInstruments #DSI #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

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Cleaning all 61 black and white keys of this P-5 Pratt&Read keyboard using an ultra-sonic bath: MUCH effective indeed! 😊😊👍👍 Anyway, there's always some manual cleaning to add after this kind of bath, in order to remove any dirt traces still present ;-) #SequentialCircuits #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #JWire #VintageSynthesizeKeyboard #PrattReadKeyboard #VintagePrattReadKeyboard #JWireKeyboard #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

One hell of a restoration project... (cont') The AM2708DC (1KB EPROMs) just arrived today... CAN'T wait to burn them and see if the Prophet comes back to life!!! (either easily, or if it still needs some Good Doctor Prager's help 😉) #SequentialCircuits #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #EPROM #VintageEPROM #2708EPROM #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

One hell of a restoration project... (cont') Very first tests after intial power-on (and before I receive blank, NOS 2708 EPROMs to burn the P-5 Rev1 software on), and after having corrected some minor issues like a reverse-installed op-amp (😡), as well as a logic chip that wasn't receiving its +5V supply because of a cut track... ...HURRAY!!! I've all the supply rails present, and I also have got a clock for the CPU to run with! Makes for a good start I guess 😊😊😊☺️☺️☺️ Can't wait for ressucitating the (front panel functionalities of) the Prophet!!! ;-) #SequentialCircuits #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager

[piscineatokyo]

One hell of a restoration project... (cont') Now let's get this Prophet-5 Rev1 front panel BLACK and WHITE... again!!! ;-) #SequentialCircuits #SCI #Prophet5 #SequentialCircuitsProphet5 #SCIProphet5 #Prophet5Rev1 #VintageAnalogSynthesizer #AnalogSynthesizerRestoration #VintageElectronics #Restoration #Repair #JohanDalgaard #StudioPiscineATokyo #TheGoodDoctorPrager