Trident battery question

[zingo]

Hello - I have a hopefully simple question: has anyone replaced the battery in a Korg Mk I Trident? The reason I'm asking is that I recently bought and repaired a Polysix with battery corrosion and then read that the Trident also uses a similar NiCd battery that should be changed. However, I can't find anything resembling the old Polysix NiCd in my Trident. Does it only apply to the Mk II version? Any help would be welcome.
Regards, Olof

[Europe Endless]

If you can wait until monday next week, I´ll pop the hood open on my MkI and have a look. I just bought the Trident and was thinking of replacing the battery myself!

[zingo]

Hello - no problem, any help would be welcome. If you find something that should be changed then I'd be grateful for the information. At the moment I suspect that the "NiCd similar to Polysix" specifically applies to the Mk II version, but then the Mk I has to have some kind of backup battery as well.

[Europe Endless]

Problem solved!
The battery is located on the KLM-292 (the largest board on the front panel) Unfortunately you have to remove the entire board from the panel, desoldering the five power connections.
Remove the old battery and put in a battery holder for a CR2032 coin cell instead. Replace R26 with a diode, cathode facing D9 (eg 1N4148) and remove C21. Remount the board and you´re set to go!

I took the opportunity to replace all the electrolytic caps and all four CMOS 4051, since I know from reparing Polysixes that they´ll fail sooner or later...

[zingo]

Thank you! Sounds like the procedure is very similar to that for the Polysix then. I'll open up the hood again sometime later this week and have a go with the soldering iron. Thanks again.