servicing little nightmare of the day !

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zamproject

Well-known member
Joined
May 11, 2010
Messages
1,503
Hi all

I'm currently servicing/restoring/repairing/recaping, whatever ...ing available, a 80' beast syth, Jupiter 8...
I take excessive care about what I'm doing on it, since market become crazy about it, and some part become hard to find.
So far only one voice dead and I find the faulty transistor network (for VCO) at local electronic shop !
Today PSU recap, I do this one inside the frame for practical reason regarding how all power are distributed, as soldered at PSU PCB.
Then I cut a tin desoldering brain extremity... jump somewhere inside despite my care to not let him fall (I don't do it on top of the frame...).
I try to find it more than one hour, I "clearly" ear it ding-ding-ing  (no visual of the fly) I also check all around on the floor
Not a sign... and don't want to power the JP8 before I put my hand on it  :(

It happen me once time ago with a capacitor(or resistor) leg in my console frame, I give up after 2 hours, it was my stuf and if a short happened, it's all on me, no problem.
This syth is not mine.

So, I just take few minute here, because when you focus to much looking for something, you usually don't find it, and the day after it's just the most visible part in the middle of the table.

Best
Zam
 
I think you'll find the brain extremity tomorrow! I use a flashlight shone along the length of the floor while looking from more directly above, to make the shadows of small objects stand out. It works sometimes. Good luck to you!  :)
 
I lost a lot of components, screws and nuts over the years.
I don't really know were all of them go when they fall on the floor!

Today it was a really really small spring from an expensive switch, without the spring the switch doesnt work.
The machine is from a client
I spent hours looking for it, removing furniture, nothing

It's probably sharing a bed with some screws and resistors
 
zamproject said:
So, I just take few minute here, because when you focus to much looking for something, you usually don't find it, and the day after it's just the most visible part in the middle of the table.

yea man, take a breather.

when you come back to it, lay a piece of white cloth on the desk, then shake the synth vigorously with the opening facing down the cloth. that'll help you spot the copper soldering braid when it's out.
 
We once had some very nice but very religious people come to record at the studio I worked in . It was something the manager had organised free of charge . The wife of the guy recording announced to us when they were leaving that she had secreted Miraculas Medals in various places in the 32 channel inline mixer ,so God would be with us and our work.
Entire console had to be stripped of its modules cleaned, inspected and the offending articals removed ,took about two days  :-X
 
metalb00b00 said:
when you come back to it, lay a piece of white cloth on the desk, then shake the synth vigorously with the opening facing down the cloth. that'll help you spot the copper soldering braid when it's out.

I already remove all card in the frame and shake them, you can't really shake a whole Jupiter 8 upside down with opened front panel...

I don't pull off the keyboard yet... maybe here  8)

Tubetec said:
The wife of the guy recording announced to us when they were leaving that she had secreted Miraculas Medals in various places in the 32 channel inline mixer ,so God would be with us and our work.
Entire console had to be stripped of its modules cleaned, inspected and the offending articals removed ,took about two days  :-X

H..Y S...T  :eek:

Once have a flood from ceiling (when I have mixing room below a flat roof), not that many, maybe one or two liter in the desk (but  more in total...)
Still same as you, pulled out all modules and disassemble them (a studer 289) and dry everything...
My luck is that I saw it, it happened when not in the studio, and when back, at the moment I want to push the power button at the back of the desk I see some water around...

Best
Zam
 
Wow lucky you spotted it ,
I got a small behringer mixer before when it was dropped back for repair to the shop I worked as a saleman in ,the owner had only bought it a week before ,someone ended up spilling a pint of Guinness right into it ,it was a write off really ,but I got it as scrap .
Once I had cleaned out all the black sticky gunk ,everything bar the meters and one aux return worked . A lucky escape for the little mixer cause Guinness is slightly conductive too, still works away now 15 years later .
 
1.  Not so bad... A producer once spilled an entire bowl of chicken soup into an MCI 500 console.  Immediate power down, cleaned with alcohol and distilled water and dried.  Operational the next day.

2.  A little more gross...  An artist spilled his chewing tobacco spit bottle into the bus assign matrix section of that same console.......

Best,
Bruno2000
 
bruno2000 said:
1.  Not so bad... A producer once spilled an entire bowl of chicken soup into an MCI 500 console.  Immediate power down, cleaned with alcohol and distilled water and dried.  Operational the next day.

nice one  8)
 
Jaysus Bruno  ;D

wasnt these guys your were recording was it ?

https://www.youtube.com/watch?v=sBYOu3xmQeI
 
zamproject said:
So far only one voice dead and I find the faulty transistor network (for VCO) at local electronic shop !
Best
Zam

Would it be possible to get me some? My buddy has a broken Jupe 8 with a couple of voices down and I'll probably end up fixing it.
 
sahib said:
Would it be possible to get me some? My buddy has a broken Jupe 8 with a couple of voices down and I'll probably end up fixing it.

unfortunately not... the guy have two pces left ... I take them both, need one but keep second one as spare.
it's the RC/CA/LM 3046 in DIP package.
You can find them a evil bay, little prohibitive, but texas still make LM3046 in SOIC package for cheap, need some adaptation.
Also you have to take care about thermal resistor compensation glued on this transistor array  ;)

Best
Zam
 
L´Andratté said:
3046 is still available

Yes there is stock around, I just say I find them cheap at 5 min by bike from my home , which save me time an money 8)
If only it could be the same for BA662, IR3109 or IR3R01 :).
So far none of those part seem broken in the JP8 I currently servicing, but there is so many... little spare will for sure be a good thing
I don't count but only for BA662 VCA there is more than 50 inside  :eek: most of them with colour key (paint) for offset matching.

Best
Zam

 
Hi

I finally give up... maybe jump outside somewhere in the room after a bounce in the JP8.
At the end the real nightmare was the calibration  :eek:
if someone around have a JP8 to service one day, be advised that it's a loooooooooonnnnnnnnnnnnnng process
I also tweak two setting, envelop now have 8 sec attack in place of 6,
and I set the VCF little more resonant  :)

Best
Zam
 
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