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First post, by root42

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My 286 is missing its CMOS battery. What are my replacement options? I do not mind soldering a bit and would love some small, elegant solution. I guess I can’t put in a cr2032 just like that due to charging.

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Reply 1 of 7, by dionb

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3x NiMH AAA gives pretty much the same voltage.

You can try a CR2032 as well, but you need a diode to prevent charging. That in turn might lower the voltage far enough below spec that the NVRAM doesn't remain stable. YMMV.

Reply 3 of 7, by tayyare

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Isn't there any external battery connector? I did not deal with any 286 boards for the last 25 years or so, but every single 386 and 486 boards with NiCad soldered batteries that I've seen had an external battery connector.

I have also found this: http://amigakit.leamancomputing.com/catalog/p … roducts_id=1093

I'm not sure if it also works with PCs (why not really?) but it's quite cheap so trying is a viable option.

GA-6VTXE PIII 1.4+512MB
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Reply 4 of 7, by root42

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tayyare wrote:

Isn't there any external battery connector? I did not deal with any 286 boards for the last 25 years or so, but every single 386 and 486 boards with NiCad soldered batteries that I've seen had an external battery connector.

I have also found this: http://amigakit.leamancomputing.com/catalog/p … roducts_id=1093

I'm not sure if it also works with PCs (why not really?) but it's quite cheap so trying is a viable option.

It has three pins, and my board needs two, but I could make my own pcb. Although it probably only has a diode on that pcb, considering the price... 😉

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Reply 5 of 7, by tayyare

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I've seen that but it's a battery at the end, and I thought why not just broke the useless (for the PC) pin and not connect it? 😊

GA-6VTXE PIII 1.4+512MB
Geforce4 Ti 4200 64MB
Diamond Monster 3D 12MB SLI
SB AWE64 PNP+32MB
120GB IDE Samsung/80GB IDE Seagate/146GB SCSI Compaq/73GB SCSI IBM
Adaptec AHA29160
3com 3C905B-TX
Gotek+CF Reader
MSDOS 6.22+Win 3.11/95 OSR2.1/98SE/ME/2000

Reply 6 of 7, by dave343

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Is it the 3.6V? On my 486 board it had a 3.6V NiCad battery that was corroded, so basically what I did was buy a battery holder with 3x 1.2V rechargeable AA batteries, and then you just solder the + & - leads onto the correct solder welds you see on the board. It's tricky but works flawless. So then the battery pack, you just use double sided tape and in my case I stuck it on the case, right above where the battery would have been. I'll see if I can upload a picture later. Do this and you'll never have to worry about replacing the battery ever again 😀

Reply 7 of 7, by root42

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There is also an Amiga blog posting about this topic:

http://www.retro-commodore.eu/2014/07/23/batt … ry-replacement/

I have checked, and my Octek Fox II has the external battery connector. The other board I was talking about doesn't.

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