Possible Repair Technique for the 80017a, the Juno-106 Voice Chip

Upfront, I'd like to say that I take no credit for inventing this technique, only for demonstrating it. I was inspired to try it by two compelling images that a person named Ramcur had posted on Flickr. I emailed him and he told me what he had done. So very special thanks to Ramcur for the method, and thanks to Chris Strellis (http://www.strellis.com) and K/Modeless Factory (http://modelessfactory.com) on the Analog Heaven mailing list for sending me sample failed chips to test this method out. Please visit their sites and patronize their services!

Some background: my HS-60 had 4 bad voices so I removed those 80017a's with plans to buy clones sometime in the future. But after I stumbled across Ramcur's photos, I tried to see if these chips could be repaired. I first used a professional heat gun, and I was able to salvage 2 of the 4 chips satisfactorially by simply removing the resin coating of the chips (the right heat allowed me to peel the coating off). But that was still only 50% yield and about 30minutes messing around with the heat gun - not easy.

After Ramcur emailed me back about using acetone, I tried it on a bad 80017 that Chris Strellis had sent me and it worked great. So I decided to create a video to show how this might be done. In the video, my HS-60 has been fitted with SIP socket to allow for quick swap out of the chips for testing. These sockets are in voice slots 2 and 3. Slot 1 has a 'known good' chip for comparison. In the final part of the video, I installed the chip that I was able to get "cleaned" in slot 2 for comparison to the good chip in slot 1 (slots 3, 4, 5, and 6 have no chips/are empty). I apologize for the bad lighting in that last part.

Does this really fix the chips? What about longer-term performance? The chips I've "rescued" so far I have put in my constantly-powered-on HS-60 for over a week and checked them twice a day and all of them no longer had any popping or cracking or cut-outs or runaway resonance or any of the classic failure modes of the 80017a. They did sound slightly different chip-to-chip, but I think that was due to me not recalibrating the trimmers for each voice.

Should you try this? I'd say you have nothing to lose and, as I show, it's pretty easy to do. If you already have a bad voice chip in your 106 or HS-60, you already would have to desolder it to install the reportedly-excellent clones from D'Naab (http://www.analoguerenaissance.com). So you could try this method first and, if it doesn't work or it's not to your liking, or you just want the comfort of something pretty much guaranteed, then you can always get the clone.

As the weeks go forward and I get time, I'll be subjecting this method to a lot of known-dead chips. I'll try to report back how that goes.

Good luck!

Category:

Music

Tags:

• synthesizer
• roland
• juno
• juno-106
• juno106
• 80017
• 80017a
• repair

[f115Recs]

Thanks for the video. That's great. What did you find over the long haul? Still working? Any more insight you have would be great.

[rolandsh1000]

@f115Recs

Most of the ones I've done have sat in a dry container for the last several months. Recently, I installed 6 of them in the HS-60 and ran them for 2 days straight with no issues.

Also, I have 6 installed in my Junior 106 (which does sit in the non-turned-on state most of the time) and they are all still working perfectly.

I'd say if you can rescue the chip and it stays good for a few days after, it's probably good for months if not years.

[Leololazone]

Hey, just bought a juno 106 and one of my keys is striking inconsistently. I think it might be a key contact and not the sound card because it's only one key. Is there any way you can point me in the right direction of where the key contacts are....under the keys I imagine, and if that's the case how do I take off the key to get in there to clean it. BTW the technique you described in your video fixed a sound card that started acting up in my HS60. Thanks!

[rolandsh1000]

@Leololazone

Hi - there's a video on Youtube that I saw a few days ago that shows how to remove and clean out the keyboard PCB for the Prophet-600 (I just got one of those!). It's VERY similar to the 106/hs60: basically, open up the synth, unscrew the keyboard chassis from underneath the synth, unplug the two connectors, pull out the keyboard, turn it upside down, unscrew the keybed PCB, and diagnose the problem. take care with the rubber domes!

glad to hear your hs60 is happy again!!!

[KlemmyConQueso]

I am asking the same question MarbleMad had...

Does anyone know if this works long term? I did it to 2 chips on an mks-30 and it worked.. I am trying to sell it. Would it be a good idea to strip the other 4? I would hate to sell it and have another chip crap out a week later, but if this fix causes other problems down the road I wouldn't be comfy with that either. I am an electronics tech so I'm not really worried about damaging anything good on removal.

[commentleaver]

Did this ruin the glass you soaked the chips in?

[Dysanfel]

Didn't work for me. My pins fell off. The coating help keep the pins on the chip.

[dzlvs8]

Thanks for sharing. Time to fix mine and get my daft punk on!

[MrFilipFischer]

HELL YES!! This method worked for me - I soaked the voice chip (80017A 40A) in acetone for 3 days removing the resin-edges of the chip on the 2nd day.

Don't remove resin that doesn't come off by itself on the component side - soak it some more. I couldn't remove the resin between the legs of the 3 IC's though soaking for 2 more days - but it still worked.

I let the chip dry for 2 days and soldered it back in. I didn't remove the harder resin from the printed resistors as someone suggested.

[MrFilipFischer]

I got the chip out pretty easily by using this inexpensive tool: Velleman VTDESOL3U Vacuum Desoldering Pump With Heater 30W.

I vacuumed each pin 2 or 3 times from the back of the PCB - only heating each pin a few seconds every time. I then used a small screwdriver to wiggle the pins gently about to loosen them (still from the back of the PCB).

After that I very, very gently wiggled the chip itself until it practically fell out. Don't use any force anywhere in this process.

[mcrh0des]

How do you know what's wrong with these chips?

Do they overheat during use?

The plastic package covering the chips is not the best heat contactor.

Do these chips have defects in silicon that becomes worse and worse

during use?

I think someone will need a very expensive piece of equipment

and a good reference datasheet to determine what's wrong with these components...

I hate disposable electronics...

[madskinnerup]

Hi!

My 106 seems to have a problem with the filter resonans after I had new voice chips. I can't seem to get all six voices to track even with keyboard tracking when the filter is self-osclating. If I set it to poly 2 mode and only use one voice at the time i am able to play simi tones with it, but when it is in poly 1 mode and I play more then one voice, the voices doesn't tune up together. Do you know how I could fix this?

[MarbleMad]

D'you think it's worth giving all your chips a chemical peel as a preventative measure or do you lean more towards the "If it ain't broke, don't fix it", philosophy?