OSCar Replacement Battery part number/type

I replaced my battery a few years ago on the advice from a tech who serviced them here in Sydney that I just use AA batteries…

Sort of makes sense in some part, because we all know if the OSCar is not turned on regularly . the battery goes flat , as its a rechargeable , and when turn on after a while, all memories are lost…

Now the AA idea , with alkaline they should last a long long time i guess, but, another Tech pointed out to me theres a circuit that is specific to recharging, and without a particular component removed, it could be bad news not having the original part.

so 2 Questions.

Battery Model Number for replacement of the original (I tossed mine)


Anyone here have schematics and point me to the part that needs removing?


I’ve never poked around inside an OSCar, but if it uses a rechargeable battery, it probably would be good to replace it with a lithium (non-rechargeable) one. The problem with the rechargeable batteries is that are prone to leaking after a period of non-use, and this leaking can destroy the circuit board. There is lots of information out there about the Korg Polysix (and Poly-61) which suffer from this. In fact, an upcoming Synth Wizards episode addresses this very issue.

To use a lithium battery, you will need to disable the charging circuit. It would be relatively simple to do, but I don’t know the specifics for doing this on an OSCar. On the Polysix, you simply remove a resistor and replace it with a diode.

Thanks for the response and insight…
Yep, thats one of the reasons I put in the AA’s Alkalines in a battery holder…To then be told by another service guy, "whoa… You need to remove… ??? " and he did mention a component, so I guess I shall scour the net for a Schematic / Service manual…

Looks like thats the better outcome…

Thanks again.
Will update with info when I have answers to help others that may find this useful.

Update: Well Ill be damned.
Scroll down to OSCar

If you have the batteries in an AA battery holder, they wouldn’t leak onto any circuitry, though. This is what I did with mine, and presumably in yours as well, because there’s no space otherwise. :slight_smile:

I have your battery replacement kit #4777 with diode. The instructions don’t specify which resistor to remove and replace with the diode. Can you give some guidance?

Do you mean to use this kit in an OSCar? That kit is for a Polysix or Poly-61, so the OSCar is not mentioned in the documentation. It looks like the battery is the right replacement for the OSCar, and I think you will just need to remove resistor R5 to disable the recharging - the diode won’t be needed. But PLEASE HAVE SOMEONE CONFIRM THIS, someone who knows more than I do about the OSCar circuitry.

It’s a Polysix…I was on the wrong string apparently…I meant to ask about the kit for the Polysix. I will continue exploring

Apparently, some of our Polysix battery kits got sent out without the instructions. If this is the case, just email sales@syntaur.com or call us (830-627-1530) and we will get these sent to you right away.