The No.1 Website for Pro Audio
Roland Jupiter 4 Battery
Old 23rd February 2020
  #1
Gear Maniac
 
markustg's Avatar
 

Roland Jupiter 4 Battery

Time to replace the original battery in my Roland Jupiter 4.

I looked on line and found two places that both wanted about $28 US in total including shipping.

It just a Nickel-Cadmium 3.6-volt, rechargeable battery , but I do not know the milliamps, as the battery is just four cells wrapped in yellow with no specs on it.

I see where some people just put in a holder for a 3.6 v coin cell that is not re-chargable, but I don't want to do that. I want to try and keep it as close to original as I can.

Anyone have any better ideas that a $28 battery?

thx

Attached Thumbnails
Roland Jupiter 4 Battery-20200223_161255.jpg  
Old 23rd February 2020
  #2
Lives for gear
 
acreil's Avatar
 

Quote:
Originally Posted by markustg View Post
I see where some people just put in a holder for a 3.6 v coin cell that is not re-chargable, but I don't want to do that. I want to try and keep it as close to original as I can.
Lithium coin cells don't leak potassium hydroxide and corrode everything though.
Old 24th February 2020
  #3
Gear Maniac
 
markustg's Avatar
 

Hmm, good point.

So would you just find some kind of holder and install a coin cell?
Old 25th February 2020
  #4
Lives for gear
 
acreil's Avatar
 

Quote:
Originally Posted by markustg View Post
Hmm, good point.

So would you just find some kind of holder and install a coin cell?
Yeah, but you have to add a diode (usually in place of a resistor or something) so that it won't charge the coin cell.
Old 25th February 2020
  #5
Lives for gear
 
Rob Ocelot's Avatar
You can use a modern cordless phone pack containing 3 NiCd AA's, 500-1000 mAH should be plenty -- I believe the original battery was 180 mAh but a larger mAh will not hurt anything. Another option is to buy a plastic 3 cell holder and use off the shelf NiCd AA. Just remember that NiCd's typically self discharge 1% per day so if you plan on leaving the Jupiter-4 idle for longer than 3 months then make sure to power it on occasionally for an hour or two just to keep the battery charged. NiCd batteries are notorious for leaking caustic if they are left idle for long periods of time which can damage copper and aluminum circuit traces and component legs. The Jupiter-4's battery thankfully resides in a pocket carved out of the wood case away from critical components unless you have a very early version. I've also seen evidence of caustic gas leakage from NiCds causing damage in areas far away from the battery of the synth but this phenomenon is far less common.

I've also used NiMH in the same format as NiCd with the advantage that the self discharge rate is much lower than NiCD -- as low as 1% per month for special low self discharge types (usually marketed under the Eneloop brand). What I don't have is data on is the long term reliability of NiMH which tend to have a low number of recharge cycles (typcially 500). The problem with a synth backup battery is that every time you power the synth on it potentially starts a new recharge cycle. There is the potential for NiMH to leak and/or outgas caustic in ways similar to NiCds though it's a fairly rare event.

I'm not a fan of bypassing the charge circuit and using 3.6V coin cells (eg. CR2032) to replace NiCd as they aren't a one-size-fits-all solution. Some types of RAM are more power hungry than others so unless you are aware of the RAM specs then you are rolling the dice as to how often you will be changing the coin cell. Not all coin cells of the same type are created equal and you generally get what you pay for (those packs of 10 at the dolllar store are tempting but I'd stay away).

For the Jupiter-4 there is also a nonvolatile RAM option . The catch is that it's part of a larger upgrade kit (IO) that may add some things that you don't want or need. Two big advantages of the nonvolatile RAM upgrade are that you gain 8 banks of 8 patches for a total of 64 (versus the standard 8 for the stock Jupiter-4) and that memory recall now restores full parameter control instead of the standard bender-only control.
Old 27th February 2020
  #6
Gear Maniac
 
markustg's Avatar
 

Thank you so much for this feedback Rob O!
Old 27th February 2020
  #7
Lives for gear
 
autoy's Avatar
Quote:
Originally Posted by Rob Ocelot View Post
For the Jupiter-4 there is also a nonvolatile RAM option . The catch is that it's part of a larger upgrade kit (IO) that may add some things that you don't want or need. Two big advantages of the nonvolatile RAM upgrade are that you gain 8 banks of 8 patches for a total of 64 (versus the standard 8 for the stock Jupiter-4) and that memory recall now restores full parameter control instead of the standard bender-only control.
Hoo boy, I wish you could still order IO. I'm stuck with CHD for the time being, not necessarily a bad thing though. I would also have to think about some kind of battery replacement, as mine sits on top of the (very early) board.
Old 1st March 2020
  #8
Gear Maniac
 
markustg's Avatar
 

So it Looks like either of these batteries would work. Sill have to figure out the best way to solder the three wires though.

https://batteryguy.com/bgnb001-3.6-v...d-battery.html

https://batteryguy.com/nickel-cadmiu...n800-3awp.html
Old 1st March 2020
  #9
Lives for gear
 
Rob Ocelot's Avatar
Quote:
Originally Posted by autoy View Post
Hoo boy, I wish you could still order IO. I'm stuck with CHD for the time being, not necessarily a bad thing though. I would also have to think about some kind of battery replacement, as mine sits on top of the (very early) board.
As far as I'm aware you can still order IO but it may take some prodding to get Lazlo to respond to emails. I've heard some rumblings of an IO 2.0 but nothing concrete.

As for that problematic battery -- if it hasn't leaked then relocating it is an option. This is what I've done for a CR-78 that (amazingly) had an intact 40 year old NiCd and no leakage. Desoldered the battery and moved it to the back of the case where there was nothing underneath it, enclosed it in a ziplock (with small holes for the leads, then resealed with tape) and suspended the bag from the rear panel with double sided tape. Probably overkill, but I wanted to monitor the rate of leakage and outgassing if the battery indeed does go. Two years later it's still keeping a charge at 3.6V and doesn't rapidly self discharge if left idle for at least a month.

It's odd that they've gone to the trouble of relocating the battery in the JP-4 when they updated the design. I've never heard of a JP-4 with a leaking battery. Ever. Not even the early revisions. Meanwhile they revised the CR-78 three times and changed to a different battery (with different charging requirements) but never moved the battery to mitigate any damage if it does leak. Sad to say, but these days I encounter more dead CR-78's from battery leakage than living ones.
Old 2nd March 2020
  #10
Gear Maniac
 
markustg's Avatar
 

Mine leaking to be sure. Green slime coming out of both ends. I am going with a 3.6V battery pack which I just ordered for about $8. I'll post a photo of the finished result.
Old 3rd March 2020
  #11
Lives for gear
 
autoy's Avatar
Quote:
Originally Posted by Rob Ocelot View Post
As far as I'm aware you can still order IO but it may take some prodding to get Lazlo to respond to emails. I've heard some rumblings of an IO 2.0 but nothing concrete.

As for that problematic battery -- if it hasn't leaked then relocating it is an option. This is what I've done for a CR-78 that (amazingly) had an intact 40 year old NiCd and no leakage. Desoldered the battery and moved it to the back of the case where there was nothing underneath it, enclosed it in a ziplock (with small holes for the leads, then resealed with tape) and suspended the bag from the rear panel with double sided tape. Probably overkill, but I wanted to monitor the rate of leakage and outgassing if the battery indeed does go. Two years later it's still keeping a charge at 3.6V and doesn't rapidly self discharge if left idle for at least a month.

It's odd that they've gone to the trouble of relocating the battery in the JP-4 when they updated the design. I've never heard of a JP-4 with a leaking battery. Ever. Not even the early revisions. Meanwhile they revised the CR-78 three times and changed to a different battery (with different charging requirements) but never moved the battery to mitigate any damage if it does leak. Sad to say, but these days I encounter more dead CR-78's from battery leakage than living ones.
Thanks, just sent him an email again. I already did this 3 or 4 times since last summer.
Old 4 weeks ago
  #12
Gear Maniac
 
markustg's Avatar
 

I ended up with the following solution that seems to be working.

3.6V niCad pack for recharable phones. 600 MaH 3 AA cells.

Velrow to the same spot where the battery was.

wire nuts to connect the pack and the cable ( in case it did not work, and also an easy change 30 years from now when it needs a new one )
Attached Thumbnails
Roland Jupiter 4 Battery-20200307_110725.jpg   Roland Jupiter 4 Battery-20200307_110018.jpg   Roland Jupiter 4 Battery-20200307_110023.jpg   Roland Jupiter 4 Battery-20200307_110844-1-.jpg  
Topic:
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump
Forum Jump