Juno 106 Voice Repair Quote

[Ianh]

Hey, sorry this is kind of a dumb question. I'm buying a Juno with a dead voice and most of the repairs i have seen are DIY but i don't have soldering equipment. Before I take it to a repair place I wanted to know around what it should cost to replace one voice chip on a 106 labor and everything. Any info would be greatly appreciated.

[schmidtc]

Roughly $100. You could also buy the chip and all the tools you'd need for roughly that price. Unfortunately, chances are if it's got one bad chip, more will fail down the road. Good luck.

[sam]

It's quite a delicate replacement ..You have to have soldering skills.

[Steve Jones]

I open and repair those chips all the time, but having said that, the new clone chips are so good that I would just go buy a couple of those, one to fix your dud voice, and a spare.

[Ianh]

Thank you all for your help, I think im going to get int DIY repairs as they are more beneficial in the long run.

[adie]

You need soldering tools, voltmeter, oscilloscope, frequency counter (or guitar tuner) to make Juno work as before. Basic knowlege of electronics is needed

[magnus]

I lack half of that equipment and have successfully repaired dead voices on my Juno several times. I think it partly depends on what course of action you take - some of the replacement chips are pretty poor imitations, and require extensive recalibration I think. However, I'm not even sure that needs more than a good ear.

Better yet, save yourself the trouble and the money by buying some acetone from a beautician's wholesaler or a chemist ("drugstore") instead of replacement chips. Chances are the problems with the chip are being caused by the resin used to coat it. If you soak the chip in acetone for a couple of days it's quite easy to remove the resin. The chip will be good as new.

My kit for the procedure would be: soldering iron, solder, solder braid or solder sucker (to help remove the chip from the board), a bottle of acetone and a sharp knife to scrape away the resin from the edges and allow the acetone to seep in.

As for basic knowledge of electronics - I'd say it only needs to be very basic: know that components will be damaged if they are exposed to the soldering iron for too long, and ICs can be fried if you touch them without grounding yourself (each of those voice chips is really a mini circuit board with ICs on it, so you should be fine if you're careful)

[Ianh]

I have done research that suggested the same and it seams like a good thing to at least try before spending 60ish bucks on new chips. I didn't however end up buying the juno with the voice problems. The guy on craigslist decided to raise the price and I didn't feel like getting j**k around. Never the less I do own a bunch of anolog equipment and i think it is time to get into repairing and building electronics. Thanks all of you for the help.

[daedalusm24]

I know this reply is pretty late coming to this thread, but I thought this info may be useful. My Juno 106 has had a bad voice chip for a while. I tried ordering a replacement chip online, and the one I received didn't work either. I saw an ebay auction for restoring all 6 voice chips, and decided to try it. I just got my circuit board back from him and it sounds perfect now. He will restore all 6 chips and calibrate all of them for $135. He strips off the coating that causes so many problems with them. Plus, if he isn't able to fix all of your chips, he will replace the bad ones, which is included in that cost. I have no affiliation with him, other than being a really happy customer. Check out his ebay auctions. His seller name is mrcoolage. I would hate to see people throwing out voice chips that can be saved.

[synth3tik]

The chips usually go for around $50-60, either pulls from other 106s or repo parts. I would get all the chips replaced as they will fail sooner or later. I myself have a 106 waiting for my buddy to get me some chips hopefully at a big discount.

[Steve Jones]

Just stripping the coating is not always enough - There is a commonly faulty jump track which needs to be bypassed, and there are certain solder joints that are often questionable as well. Some modules had the jump track hand bypassed before encapsulation. You can usually get them going again, sometimes there is a chip fault and in that case replacement is the only solution.

If your desoldering skills are good enough that you don't lift tracks on your voice board, then fixing the module is definitely worth a try.

[cornutt]

You can replace the chip with just a soldering iron and a solder-sucker. However, you will probably have to calibrate the synth afterwards. And to do that properly, you really need a scope -- there are a couple of steps where you have to set the peak-to-peak voltage of a waveform, which you obviously can't do by ear. I don't find the frequency counter to be necessary, though. I tune the VCF to the DCO (make sure the DCOs are in tune before you start).

[SickMonkey]

I've been able to calibrate them reasonably well with only a voltage meter. On steps 5 and 6 in the service manual (VCF Resonance and VCA Gain), just make sure all chips have the same voltages (if you're only replacing one or two chips, you can use the others for reference).

As for repairing the chips, about 50% seem to be cured by the acetone bath. From the ones still defective after that, reheating the solder joints will fix another third or so. Haven't actually made any statistics, but i've done it on about 30 chips in total.