- It is currently Thu Apr 11, 2024 8:23 am • All times are UTC + 10 hours [ DST ]
Juno 106 voice chip issues...
Moderators: Thirteen, rick, Mark Bassett
29 posts
• Page 1 of 1
Juno 106 voice chip issues...
So I got the Juno fired up after a few years in storage. I was sitting here this morning playing the start to Van Halen's Jump. I put the Juno into mono mode then when i went back to poly1 one voice started acting up, then pretty much crapped out. I did the diagnostic mode and it is chip 6, all good I can deal with that. But, chip 4 is down in level and quite dull compared to the others. Anybody know - Is this a sign that this voice chip is going bad as well or just a calibration issue?
Thanks.
Thanks.
Andy Evans
http://www.mud.net.au
http://www.mud.net.au
-
Chinagraf - Valued Contributor
- Posts: 1608
- Joined: Wed Jun 22, 2005 1:09 am
- Location: Melbourne
Chinagraf wrote:I was sitting here this morning playing the start to Van Halen's Jump.
Might not the Juno simply be making an aesthetic protest?
Chris Preston
The man who gives meaning to the word "amateur"
The man who gives meaning to the word "amateur"
-
chris p - Frequent Contributor
- Posts: 882
- Joined: Tue May 10, 2005 6:15 pm
- Location: Sydney, NSW
chris p wrote:Chinagraf wrote:I was sitting here this morning playing the start to Van Halen's Jump.
Might not the Juno simply be making an aesthetic protest?
oh touché chris
wez prictor
composure music
http://www.composuremusic.com.au/
Australian importer of Crumar Mojo keyboards & accessories. Vintage keyboard fetishist.
composure music
http://www.composuremusic.com.au/
Australian importer of Crumar Mojo keyboards & accessories. Vintage keyboard fetishist.
-
wez - Valued Contributor
- Posts: 1259
- Joined: Fri May 06, 2005 10:38 pm
- Location: Slightly to the left.
Bahahahaaaaaaaaaaaaaaaa
#&^% you Chris :P
(it was a good one though)
I don't care cause i get up an nothin gets me down
#&^% you Chris :P
(it was a good one though)
I don't care cause i get up an nothin gets me down
Andy Evans
http://www.mud.net.au
http://www.mud.net.au
-
Chinagraf - Valued Contributor
- Posts: 1608
- Joined: Wed Jun 22, 2005 1:09 am
- Location: Melbourne
Yes, two bad chips. If you really like the synth, get a set of new clone chips and put them in, and never have to worry again. Otherwise, remove them, soak them in acetone for a couple of days to get the conformal coating off, gently resolder each of the edge pins, adding some extra solder to each, and solder a piece of fine wire to bypass the jump track on the third edge connector pin from the right to pin 15 of the IR3109 IC, and you may well be fine after that until another one goes (and it will).
Steve Jones
-
Thirteen - TRM Endorsed
- Posts: 1279
- Joined: Fri Dec 01, 2006 5:08 pm
- Location: Sydney
Thanks for the advice Steve. If you wouldn't mind, could you elaborate on the jump track bypass please? Is it the 3rd pin form the right of the voice chip as you look at the front, right way up? Is the IR3109 IC on the actual voice chip? I'm hunting a schemo at the moment, so maybe that will answer some of the questions.
THanks again.
THanks again.
Andy Evans
http://www.mud.net.au
http://www.mud.net.au
-
Chinagraf - Valued Contributor
- Posts: 1608
- Joined: Wed Jun 22, 2005 1:09 am
- Location: Melbourne
Re: Juno 106 voice chip issues...
I have decided to undertake the Acetone method of VC recovery. I also have two dead chips (#1 and #6) and currently can't afford the Analogue Renaissance chips or to have a synth tech restore the chips for me. I've never soldered in my life and have no knowledge of electronic circuitry so I'll be going off of information on the web as to how to undertake this procedure. This will be a learning exercise for me and I'll post pictures onto a separate thread of how I go once I get my hands on some acetone (housemate has a soldering iron thankfully) and some fine wire from Jaycar or the likes.
Depending on how involved doing the two chips turns out to be (and as long as I don't solder myself to my synth (one at last!)), I may do the other 4 currently working chips as well while I'm at it, considering they're all bound to die at some stage anyway...
Andy, if you're intending to undertake the same procedure and get to it before me I'd appreciate sharing notes with you.
Thanks,
Michael
Depending on how involved doing the two chips turns out to be (and as long as I don't solder myself to my synth (one at last!)), I may do the other 4 currently working chips as well while I'm at it, considering they're all bound to die at some stage anyway...
Andy, if you're intending to undertake the same procedure and get to it before me I'd appreciate sharing notes with you.
Thanks,
Michael
Michael Callanan
[insert witty slogan here]
[insert witty slogan here]
-
tweakeasy - Registered User
- Posts: 228
- Joined: Thu May 21, 2009 2:54 pm
- Location: Sunshine Coast
Re: Juno 106 voice chip issues...
If you are going to use desoldering braid, the best one that I have found is the one sold by Jaycar, it's Japanese and it wicks very well. The purple coloured roll is a good size. Those spring loaded solder suckers are next to useless.
Steve Jones
-
Thirteen - TRM Endorsed
- Posts: 1279
- Joined: Fri Dec 01, 2006 5:08 pm
- Location: Sydney
Re: Juno 106 voice chip issues...
Thanks Steve, I've made a note of it. Also wanted to ask - how many days have you found to be optimum for the acetone soak and is there a danger of over-soaking them? (as in potential damage to the chip).
Thanks,
Michael
Thanks,
Michael
Michael Callanan
[insert witty slogan here]
[insert witty slogan here]
-
tweakeasy - Registered User
- Posts: 228
- Joined: Thu May 21, 2009 2:54 pm
- Location: Sunshine Coast
Re: Juno 106 voice chip issues...
There seem to be 2 different coatings - some come off fine after about 36-48 hours, some can take another 24 hours. Pull them out now and then and see.
Steve Jones
-
Thirteen - TRM Endorsed
- Posts: 1279
- Joined: Fri Dec 01, 2006 5:08 pm
- Location: Sydney
Re: Juno 106 voice chip issues...
Well I've achieved the easy lead-ups to the scary part…
• Acetone - 500ml 3M brand from Supercheap $10.95
• Desolder braid - (purple roll) from Jaycar - brand is 'Goot' 2mm $5.95
• Identified dead voice chips by running synth in diagnosis mode – chip #1 showed to be completely dead whereas #6 was just a little quieter than the rest but probably a sign that it’s on its way out so will do it too, then the remaining 4 when I have more time.
• Removed the two topmost screws at either end of the board to open up the synth
• Took photo of module board to ensure I’d plug everything back in where it goes (though it’s all pretty obvious as the plugs stay around their homes once removed)
• Carefully unplugged the 5 white connecting plugs from the module board
• Removed the 6 screws holding the module in place
• Removed module board.
Now... looking at the soldering points of the chip’s connector pins on either side I realize how delicate a job it will be removing them from the board with a soldering iron. This is a problem for me because a) the soldering iron I planned to borrow from my housemate is for medium-sized soldering and will be a bit clunky for such precise work (and I’d probably end up damaging the module board itself!) and b) my aforementioned complete lack of soldering experience… so I’ve contacted a friend who’s a wiz at circuit bending, building his own pedals and electronics in general and had previously offered his soldering skills to help me. This will be a good opportunity to learn by watching someone experienced doing it and then I’ll practice on the guts of some old hi-fi equipment I have at home and purchase my own finer soldering iron to do the remaining 4 chips.
Apologies for the essay-length entry…
• Acetone - 500ml 3M brand from Supercheap $10.95
• Desolder braid - (purple roll) from Jaycar - brand is 'Goot' 2mm $5.95
• Identified dead voice chips by running synth in diagnosis mode – chip #1 showed to be completely dead whereas #6 was just a little quieter than the rest but probably a sign that it’s on its way out so will do it too, then the remaining 4 when I have more time.
• Removed the two topmost screws at either end of the board to open up the synth
• Took photo of module board to ensure I’d plug everything back in where it goes (though it’s all pretty obvious as the plugs stay around their homes once removed)
• Carefully unplugged the 5 white connecting plugs from the module board
• Removed the 6 screws holding the module in place
• Removed module board.
Now... looking at the soldering points of the chip’s connector pins on either side I realize how delicate a job it will be removing them from the board with a soldering iron. This is a problem for me because a) the soldering iron I planned to borrow from my housemate is for medium-sized soldering and will be a bit clunky for such precise work (and I’d probably end up damaging the module board itself!) and b) my aforementioned complete lack of soldering experience… so I’ve contacted a friend who’s a wiz at circuit bending, building his own pedals and electronics in general and had previously offered his soldering skills to help me. This will be a good opportunity to learn by watching someone experienced doing it and then I’ll practice on the guts of some old hi-fi equipment I have at home and purchase my own finer soldering iron to do the remaining 4 chips.
Apologies for the essay-length entry…
Michael Callanan
[insert witty slogan here]
[insert witty slogan here]
-
tweakeasy - Registered User
- Posts: 228
- Joined: Thu May 21, 2009 2:54 pm
- Location: Sunshine Coast
Re: Juno 106 voice chip issues...
Thirteen wrote:Those spring loaded solder suckers are next to useless.
I used to think so also, and swore by wick, but recently I found another brand (Spring loader solder sucker) in my stuff, and it is a killer - really awesome.
It's got me through a few jobs swiftly that wick would have taken me ages.
Cheers
Mike
Mike de Vrees
Purveyor of old stuff
Purveyor of old stuff
-
Futureman - Frequent Contributor
- Posts: 994
- Joined: Wed Mar 19, 2008 4:47 pm
- Location: Sydney
Re: Juno 106 voice chip issues...
So like most things desoldering the chip from the board was nothing as hard as I'd built it up to be - just very time-consuming. We used a combination of the wick and a spring-loaded solder sucker (blue anodized ones from Jaycar) and it (eventually) came out quite cleanly. The process should get a bit easier/quicker by the time I get to chip #6... but for now I'm just concentrating on #1 (the worst of the bunch) and it's soaking in acetone right now. I'm really enjoying learning these basic things and if the recovery process is a success I'll enjoy it even more! Meanwhile we're doing some perverted circuit bending of an old Casio and I'm admiring my friend's home-made spring-reverb unit which he's built into a Taylor's wine box.
Michael Callanan
[insert witty slogan here]
[insert witty slogan here]
-
tweakeasy - Registered User
- Posts: 228
- Joined: Thu May 21, 2009 2:54 pm
- Location: Sunshine Coast
Re: Juno 106 voice chip issues...
Hey Michael, just saw this... I did two chips in mine but I have a desoldering station so it was easy to remove them. People with wicks usually load the pins up with solder first.
It took about 3 days for the coating to come off but some had to be peeled off, it didn't just fall off by itself. Then I used a toothbrush in acetone to clean around the finnicky .
After putting them back in I had one chip that was still a little strange, so I ordered a clone from Dnaab. AS soon as it arrived the chip in there came good and so far has behaved,
but at least I have a clone as a backup. Now would be the time to order some while the dollar is high.
Cheers.
It took about 3 days for the coating to come off but some had to be peeled off, it didn't just fall off by itself. Then I used a toothbrush in acetone to clean around the finnicky .
After putting them back in I had one chip that was still a little strange, so I ordered a clone from Dnaab. AS soon as it arrived the chip in there came good and so far has behaved,
but at least I have a clone as a backup. Now would be the time to order some while the dollar is high.
Cheers.
Andy Evans
http://www.mud.net.au
http://www.mud.net.au
-
Chinagraf - Valued Contributor
- Posts: 1608
- Joined: Wed Jun 22, 2005 1:09 am
- Location: Melbourne
Re: Juno 106 voice chip issues...
Chinagraf wrote:Hey Michael, just saw this... I did two chips in mine but I have a desoldering station so it was easy to remove them. People with wicks usually load the pins up with solder first.
It took about 3 days for the coating to come off but some had to be peeled off, it didn't just fall off by itself. Then I used a toothbrush in acetone to clean around the finnicky .
After putting them back in I had one chip that was still a little strange, so I ordered a clone from Dnaab. AS soon as it arrived the chip in there came good and so far has behaved,
but at least I have a clone as a backup. Now would be the time to order some while the dollar is high.
Cheers.
Hi Andy, yeah it took the same length of time for me to get all the black crud off chip 1, likewise used a toothbrush dipped in acetone to get the last little hangers-on. Used a sharp edged micro-sized flathead screwdriver to do the careful lifting off before hand. Worked well. I'm giving the inside of the synth a good clean while it's open and hopefully will get to my mate's to re-solder the chip back in in the next couple of days. Will let you know how it went. Will decide from there depending on outcome if I need some clones... Hopefully not!
Cheers
Michael Callanan
[insert witty slogan here]
[insert witty slogan here]
-
tweakeasy - Registered User
- Posts: 228
- Joined: Thu May 21, 2009 2:54 pm
- Location: Sunshine Coast
Re: Juno 106 voice chip issues...
Re-flow and add solder to all of the silver pins along the base of the chip. If the chip does not work after all this, you may need to install a wire bridge across the jump track on the -15V rail if the chip batches were either 41C or 42B (I guess I should have gotten you to check the batch number before you removed the conformal coating)
Steve Jones
-
Thirteen - TRM Endorsed
- Posts: 1279
- Joined: Fri Dec 01, 2006 5:08 pm
- Location: Sydney
Re: Juno 106 voice chip issues...
Thirteen wrote:Re-flow and add solder to all of the silver pins along the base of the chip. If the chip does not work after all this, you may need to install a wire bridge across the jump track on the -15V rail if the chip batches were either 41C or 42B (I guess I should have gotten you to check the batch number before you removed the conformal coating)
All my chips are 40A except chip #6 which is 50B so I'm assuming that's been replaced by Roland back when they were still making them.
Michael Callanan
[insert witty slogan here]
[insert witty slogan here]
-
tweakeasy - Registered User
- Posts: 228
- Joined: Thu May 21, 2009 2:54 pm
- Location: Sunshine Coast
Re: Juno 106 voice chip issues...
Just reinstalled #1 chip and it worked perfectly. So now onto #6 for the same treatment. During a Wave Form Test #5 pitched higher than the rest. Hoping that's an easy adjust by pitching it down via the corresponding trim pot, (probably not), reading about it now... Learning stuff... slowly...
Michael Callanan
[insert witty slogan here]
[insert witty slogan here]
-
tweakeasy - Registered User
- Posts: 228
- Joined: Thu May 21, 2009 2:54 pm
- Location: Sunshine Coast
Re: Juno 106 voice chip issues...
Yeah you can but the pots for each voice aren't numbered sequentially. Do you have the service manual?
If not the one for voice 5 is VR 9
If not the one for voice 5 is VR 9
Andy Evans
http://www.mud.net.au
http://www.mud.net.au
-
Chinagraf - Valued Contributor
- Posts: 1608
- Joined: Wed Jun 22, 2005 1:09 am
- Location: Melbourne
Re: Juno 106 voice chip issues...
Nay I didn't, thanks mate!
Michael Callanan
[insert witty slogan here]
[insert witty slogan here]
-
tweakeasy - Registered User
- Posts: 228
- Joined: Thu May 21, 2009 2:54 pm
- Location: Sunshine Coast
Re: Juno 106 voice chip issues...
Oscillator pitch is not adjustable per voice, so I assume that you mean the VCF pitch at self oscillation, which will be a trimmer adjustment.
Steve Jones
-
Thirteen - TRM Endorsed
- Posts: 1279
- Joined: Fri Dec 01, 2006 5:08 pm
- Location: Sydney
Re: Juno 106 voice chip issues...
Steve is right, that is VCF frequency. I was getting it confused with my JP-4, which you can trim the individual pitches on.
Andy Evans
http://www.mud.net.au
http://www.mud.net.au
-
Chinagraf - Valued Contributor
- Posts: 1608
- Joined: Wed Jun 22, 2005 1:09 am
- Location: Melbourne
Re: Juno 106 voice chip issues...
Chinagraf wrote:Steve is right, that is VCF frequency. I was getting it confused with my JP-4, which you can trim the individual pitches on.
Wish I had a JP-anything to get confused with. Thanks for that, duly noted. Reinstalled the second recovered chip last night, likewise worked beautifully! Spent many hours into the night tweaking in delight.
Michael Callanan
[insert witty slogan here]
[insert witty slogan here]
-
tweakeasy - Registered User
- Posts: 228
- Joined: Thu May 21, 2009 2:54 pm
- Location: Sunshine Coast
Re: Juno 106 voice chip issues...
Do you still need any chips ?
I don't usually read the synth page , but did today. I worked at Roland service Dept in the late 80s (even worked on Nymo's old Jupiter 8 with Midi mod on the DCE bus) . Anyway I have a number of voice chips for the old Junos that I kept for a rainy day ( all still virgin). What chips are you after ?
I don't usually read the synth page , but did today. I worked at Roland service Dept in the late 80s (even worked on Nymo's old Jupiter 8 with Midi mod on the DCE bus) . Anyway I have a number of voice chips for the old Junos that I kept for a rainy day ( all still virgin). What chips are you after ?
Alastair Reynolds
Broadcast Radio Engineer
Master of the Dark Arts (Broadcast)
Broadcast Radio Engineer
Master of the Dark Arts (Broadcast)
-
Alastair Reynolds - TRM Endorsed
- Posts: 475
- Joined: Mon Dec 04, 2006 1:51 pm
- Location: Sydney
Re: Juno 106 voice chip issues...
Alastair Reynolds wrote:Do you still need any chips ?
I don't usually read the synth page , but did today. I worked at Roland service Dept in the late 80s (even worked on Nymo's old Jupiter 8 with Midi mod on the DCE bus) . Anyway I have a number of voice chips for the old Junos that I kept for a rainy day ( all still virgin). What chips are you after ?
I'd take any as spares or for future fixes to keep my Juno alive or for other machines I pick up! PM me what you have and what you want for them and we'll work something out. Thanks Alastair!
Michael Callanan
[insert witty slogan here]
[insert witty slogan here]
-
tweakeasy - Registered User
- Posts: 228
- Joined: Thu May 21, 2009 2:54 pm
- Location: Sunshine Coast
Re: Juno 106 voice chip issues...
Alastair Reynolds wrote: I worked at Roland service Dept in the late 80s (even worked on Nymo's old Jupiter 8 with Midi mod on the DCE bus)
You mean the MD8 midi-to-DCB converter? Or was there a custom job?
-
a.d.a.m. baby - Registered User
- Posts: 219
- Joined: Tue Sep 15, 2009 11:49 pm
- Location: Gold Coast
Re: Juno 106 voice chip issues...
Nah, not an external Box. From memory (we are talking over 20 years ago) there were 2 or 3 MIDI/DIN sockets mounted on the back of the case next to the DCB socket then wired on multicolour ribbon cable down to the board. I remember it because it was the only one we'd ever seen. And of course it sounded great
Alastair Reynolds
Broadcast Radio Engineer
Master of the Dark Arts (Broadcast)
Broadcast Radio Engineer
Master of the Dark Arts (Broadcast)
-
Alastair Reynolds - TRM Endorsed
- Posts: 475
- Joined: Mon Dec 04, 2006 1:51 pm
- Location: Sydney
29 posts
• Page 1 of 1
Who is online
Users browsing this forum: No registered users and 1 guest