Hello. Another awesome video, loving the process. Just a little note. Those three "chips" are actually waveshapers (converting square comming from digital logic to saw, pulse/pwm and sub osc) and rest 6 are VCF+VCA all in one. All the best!
I had seen them referred to both as "wave chips" and "filter chips." After I had made this video, I saw that they are in fact called "waveform" chips in the service manual, where the voice chips are called "VCF/VCA" chips, so you're right.
Wiggling chips can be dangerous with older synths… Some boards are very delicate and the pads can come off with the legs because a little piece of solder was still attached…
When you have SIP chips like this where you have a lot of legs, the ones that are free aren't attached, and you're identifying which ones do still need to be desoldered. You don't want to wiggle it enough that you would lift a pad still attached to a pin.
Hi Scott, Man you hooked me up! Just seeing you removing that CPU made me nerveus, lol. I did some DIY electronics when i was around 15-20 years old and this braught back memory's. You even got me to the point that if i had the money to buy this synth and do the same restoration i would. Great work and i hope that the synth will work great when you're all done and good to go. See you in the next episode ;) Cheers from Belgium! Johan
Brilliant... this should have been done eons ago.. such a useful video cause when i sit with my tech in future I will know exactly what needs to be done. Thank you Scott!
This was really helpful! I've replaced all wave generator and voice chips with the Analogue Renaissance clones on my 106 but I still have one voice completely silent and one where the cutoff frequency has no effect. Everything else is fine...Oh and the new Xvive chorus chips are much quiter than the old ones!
Excellent video series, Scott. I noticed you had to use quite some force to seat the Kiwi Quick socket into the 4 rows of pins. One tip I've learned from DIY'ing numerous Eurorack modules, is to first attach the socket's to the chip. Then place the chip plus socket into the pcb and finally solder the thing down. So in your case, you could have attached the four SIL rows to the Kiwi board first and then soldered it down.
True...but I would have had to know in advance that they were going to be that stiff! :) Also, I don't know that I would have wanted to push those sockets on if they were that stiff, I likely would have ended up bending pins. Ah well, I only had to do it once.
Thank you so mouch for this video. Huge hjelp while upgrading my voice and filter chips. 👍👍👍👍👍 Do not think i have to do the calibration knop thing. Sounds good at the moment😁 Angus
I am a subscriber who subscribes to your RU-vid in Korea. I am always grateful for the great content that the title of 'Professor of Synthesizer' would suit. I also have a juno-106 and it seems like the voice chip is broken, but I am sad that I can't even think of fixing it and it's hard to get parts
this is such an amazing video! thank you so much. can you teach how to replace a cracky 1/4 inch crapy output? or is that just fixed with some deoxit5?
I just found a local 106 and jx-8p for sale but not sure I want to pull the trigger as I'm not 100% sure on their condition, and if I did I would definitely like to replace with the Kiwi chips and any questionable voice chips/capacitors etc.... Do you know of any reputable places online where you could send these old synths for restoration/repair?
Hi Scott. Thanks for your insight in your videos. I have a Korg Kross 2 / 88 key. Ofentimes the sound drops completely as I'm playing. Then I just tap on any key, and then the sound comes back again. Could that be some kind of sound generator that's malfunctioning? The sound drops out on a regular basis. Now I just expect it to happen. It's like a normal issue that won't go away. The sounds play normal for around 5 to 10 minutes, before all of a sudden it drops back out. I was wondering what could you suggest that may be causing the sound to drop out? I thought, hopefully I may be able to fix it myself. I appreciate your insight. Thanks always.....
Really depends on what is causing it to drop out. I'd try wiggling the audio output wires and see if that causes it. You have to narrow down just what is causing the dropouts.
Thanks Scott. I have a Juno that belonged to my late brother. I’d love to get it working properly again, and thanks to these videos, I reckon I’ve got the confidence to try to do it myself.
If you want the truth...I was out of flux!! :) I had just thrown my empty container away a couple of weeks prior, and hadn't bought more. I have a solder pot that I use for tinning wires, and you have to apply flux first or it doesn't flow, so I usually have lots on hand...but not that day, unfortunately. I was hoping the flux core in the solder would be enough...
If the device in question is not going to be saved - a safer method to prevent heat related damage to the pc board and traces is to cut all the leads off the chip close to the chip body. This removes the device as a heat sink to your desoldering device whether that be iron, rework station, soldapult, etc. Basically, the desoldering then becomes only one lead times the number of leads that need to be individually extracted.
If we already used the acetone to clean all our chips and they are in there bare but all working still, is there anything you can paint on the chips now that prevents those resistors from beibg exposed and degrading like you say?
If there is, I haven't heard about it. Most everyone I have heard about who stripped the epoxy, just left them bare. The problem is...finding something that won't affect the chip and resistors, won't degrade, won't allow moisture.
Thanks for this video! Extremely helpful. I seem to be having difficulty removing the connectors from the voiceboard. Do I need to squeeze the tabs in or something? I don't want to break anything. Thank you!!!
Scott, excellent videos and thank you for posting all the links that you do. Could you please tell me if you actually use the Yihua 948 desoldering pump and is it a good buy ?
I use one that is *almost* identical to that one, except without the second soldering iron, as I already have a temperature-controlled soldering iron station. It has been working great for me for quite some time, although like you see in the video, you DO have to keep it clean.
You see me soldering in CPU headers starting at 21:48 - those are soldered into the board, and then the CPU interface plugs (very firmly) into those headers.
@@ScottsSynthStuffAmazing! You did such a wonderful job with this repair/mod and the video series is so well-produced. Thanks so much for all this great information. I can’t imagine the amount of work that went into this.
This further cements that should I ever decide to own a Juno-106 to make sure the voice chips have already been replaced. The amount of labour involved in restoring them is nuts!
@ghost mall I know just enough about how to do these things that it's dangerous. I know how to desolder, solder, etc. but lack the proper tools - which are expensive - to complete the job efficiently and well. It would also sit on the pile of ever-growing projects that I mean to get around to but never do. Like you I'd much rather pay a tech to do it right the first time, do it quicker than I would and also not have to fix my mistakes. The problem is finding a good synth tech in certain parts of the world can be troublesome and if you do, they're often backed up for months on end due to high demand. I've had stuff sitting with my guy for over a year!
I have a big pot of flux on my bench, but a lot of the time on these 40-year-old boards that were wave soldered, the solder is old and doesn't heat well. That's why you see me repeatedly adding new solder over top of the existing joints, then using the pump to suck it all up at once.
