Backup RAM Battery Mod for a Turbo Duo

[NightWolve]

Anybody ever try replacing the capacitor that preserves your saved states with a Lithium type battery that'll last 10 years ? Any info around on how to do this for a US Turbo Duo specifically ? Weird thing, my saved states were around for years even without a 3 month recharge by turning the unit on (I left the unit alone for many years), but recently it lost all the saves, specifically the Ys IV ones that I had which could've been useful for jumping to parts of the game for testing the upcoming dubbing work...

https://www.pcengine-fx.com/forums/index.php?topic=7517.0

I did search around before posting, only found the above thread. It talks about the capacitor in question, but not the idea of somehow replacing it with a Lithium type battery. I assume with such a mod you'd have to get the right voltage and sever the trace that sends power to the old cap position, since you wouldn't want it recharging a non-rechargeable battery when the system is powered on.

[SignOfZeta]

I'd rather have the capacitor.

[bust3dstr8]

You could try using a NVSRAM. Then you wouldn't need to worry about the cap or battery 

ifc...the Duo uses a 32k X 8


http://www.cypress.com/?docID=34283

[Keith Courage]

You could just use a TENNOKOE BANK card for the saves that you want to keep for a long time and don't want to worry about loosing.

[thesteve]

if the saves were lost when the unit had been recently used, the issue is not the cap discharged.
the cap is the upgrade for the nicd battery (as seen on old PC motherboards)
i have equipment at work based on lithium batt in chip NVRAM and its down due to battery failure.
the batt may be good for 10years on the shelf, but not when powering chips.

[NightWolve]

The ~10 year guesstimate is based on my PS2 and the 3V CR2032 Lithium battery that it relies upon for storing configuration changes and maintaining the system clock. It lasted about ~10 years, just about - had to change it recently. Also, I got a gold Zelda cart and noticed I still have a saved game that shows up - pretty sure they used a CR2032 for that as well. I realize though it'd be unpredictable as to how much longer this memory chip would last since it likely consumes more power compared to the above cases, but I'm, eh, mildly interested in the idea.

Anyway, anybody know where is the cap in question and what is its voltage ? Would this idea even work, is it safe ?

if the saves were lost when the unit had been recently used, the issue is not the cap discharged.

Well, maybe that cap and the rest are coming to the end of their lives.

[grahf]

Not worth it in my opinion. Most Duos hold save data for months or longer with the stock cap, sometimes longer. I think the ultimate mod would be to just replace the cap with a higher capacity one.