Mandatory viewing for anyone who wants to maintain, refurbish or just clean an old SY77/SY99!!! One note: if you go to the considerable trouble of dismantling the device, it makes sense to replace all electrolytic capacitors with new ones. A dry capacitor can cause semiconductor components/micro-chips to fail (usually when the synth is switched on), and that may be fatal/irreparable. There are also very useful aftermarket parts such as USB floppy emulators, better displays, additional ROM memory, replacement push-buttons etc. that can be fitted as part of this process - my SY99 has even been fitted with encapsulated precision potentiometers for pitch and mod wheels. SY77/SY99 are absolutely fantastic synthesizers, among the finest ever built, and very well worth the effort!
Thank you for this video! It was immensely useful to me. My cat peed on my SY77 (😖UGH!) so I had to disassemble it to clean. Every single detail in your video was extremely helpful for me to remember where each connector and circuit board goes. I can't say I'm confident about what I did, there's something wrong with the way it sounds now, but I think I might have switched the keyboad connectors when reassembling. I'm gonna take a look at it now, and here I am back to your vid! Can't thank you enough!!!
I watched this again because I picked up a W5 which uses the same keys and it had a couple that were broken. I remembered that this video had some good footage on fitting the keys which was good to watch before attempting it myself. I also subscribed this time :)
This is very helpful. Full watch here. I just purchased an SY-55. The keys are fairly dirty, although they all play well. And the left-hand endcap snapped off in shipping. Otherwise it seems great, fantastic, but the keys and case need a bath. I've also got an SY22 with a few keys that do not spring up. I'd love to make them both tip-top. Thanks for posting the whole process. It's great to know what to expect. Cheers from NY, USA!
I just replaced the LCD screen on my SY-77 with on I bought at Mouser. I had to do some modifications to the power that supplies the LCD backlight and modify the circuit the adjusts the contrast. When I made the nods I deicded to remove and clean all the keys. It would have gone great except for two things. I did not remove the trigger board as you did, so when I reinstalled the keys I bent about 10 of the trigger contacts. I was very upset. I did fix them but now I have a new problem. Most of the sounds are now messed up. Even the facotry presets. I believe it is something to do with what creates or modifies one of the AWM sound engines. I am still in the process of trying to figure out what I might have done. Grrrrr!!! Great video, by the way!
@ <a href="#" class="seekto" data-time="1374">22:54</a> "Bubbles" on the LCD screen has been caused by the unit being exposed to direct hot sunlight. The membrane that covers the glass component of the screen "degasses" the layer of glue under that membrane and when its exposed to heat for too long, it forms bubbles. It can be fixed IF you have the hands of a surgeon and get a VERY sharp hobby knife with a hair dryer heating the area up and gently prick a hole and then massage the gas out with a credit card with some fine microfibre cloth wrapped around the card. There's really nothing else that would fix the problem apart from getting a new display. So, you don't have really anything to loose. You just have to be careful NOT to chip the glass underneath the membrane. I have an SY77 myself with the same problem and I got the big ones out fine and the smaller ones I tried to push them to the closest edge. Was a lot better than when I first got it.
The SY77 appears to have the same keyboard assembly as a Korg M1 (or more correctly, the other way around as my M1 keyboard PCB is branded as Yamaha)... those key contact leaves (@ <a href="#" class="seekto" data-time="1302">21:42</a>) are tricky to service as they can easily fold under the key as you reinstall the key back into the chassis... take lots of care doing this and go slowly.
You had a great opportunity to replace that dim LCD with a nice bright one. Also it probably is not too hard to find new replacement keys. Would have increased the value.
I have an SY77 which I've had since 1990 and I've been searching now through the internet for quite some time now after someplace or someone who might know how or where to replace this... fucking tiny battery thing! And then - I come across THIS video with THIS guy!? Dismantling the whole bloody thing like nothing! I couldn't DARE to do HALF of it - even if I played the video in slow motion a hundred times over! And he goes "didn't get all the screws back in" - oh you don't say!? But then again, I'm quite the opposite of a handy-man. Amazing to watch anyway, I do say! Now, I know this is an old synthesizer and it would probably be both cheaper and - most likely - smarter for me to buy a brand-new MIDI master keyboard altogether, considering all the new features of today but.... I liked (still do) the keys on it. It has sort of a special weight that I like. But I suppose the more annoying part is that I was hoping to make a digital recording of some old tunes I made with it long ago. Well, providing that the old the sound data/samples would still be intact that is, which I'm not sure they would - even if you replace the battery, as I understand it. In any case, I'm not shipping the damn thing to Japan! ; )
Wonderful video! Thanks for sharing your expertise. I`m considering buying an SY77 which has one broken White Key. Do you think it`s possible to replace it without disassembling everything as you did in this video? Whilst I am reasonably practical I lack the confidence to do an entire strip down. Kind regards
Nice video, I just tried fixing a key on my yahama SY22 in which was successful but now all the C keys are not producing sound any advice. Should I clean the contact strip???
The battery resets the transposition and it is so high if you don't set it to zero you will hit keys and there will be no sound. It part of the main boot settings that resets when you cycle the power by shutting the machine off and turning it on again. Once there is a new battery on the main board you can set its zero and you won't have to do that again
Doing this full restore myself. I found only 2 very small metal spacers and have no idea where they came from! I’ve looked through the video but can’t find note of it. Do you happen to remember where these 2 little washer/spacers went? 😅
the screen damage seems like impact damage, three points, kind of equidistant from each other, might have well been something with metal prongs that first impacted, then scratched the screen?
About the display scratches... I have seen those displays with some deformation/bubbles on them, but it was from factory that way. Perhaps someone thought it was some glue and tried to get it out
I bought one and it is in a sorry state. 3 or 4 keys broken, holes in the back and dirtier than a sailor's mouth. Probably paid too much for it but I kinda wanted it.
