LisaList2

General Category => LisaList2 => Topic started by: compu_85 on October 24, 2020, 07:59:44 pm

Title: I/O Card NICD Configuration
Post by: compu_85 on October 24, 2020, 07:59:44 pm
The prior owner of my 2/5 removed the battery pack when he got it in 1997... a good thing as corrosion had already started.

I'd like to install a supercap on the board so that if the power is unplugged for a moment the clock keeps going - yes, I know this won't run for long. I'm looking for ~30 sec of runtime.

When I measure the battery terminals I get 2.6v. Was the original pack 2 strings of 2 cells, or 4 cells in one string?

Thanks,

-J
Title: Re: I/O Card NICD Configuration
Post by: rayarachelian on October 24, 2020, 09:31:55 pm
Was 4 NiCAD cells in series, likely 1.2V each, so not quite 5v. Instead of doing that, you could run a pair of wires outside of the case and attach it to a 4 pack of NiCADs. If they leak, they're external and won't damage the Lisa.

I've done similar things with the weird Lithium battery that's used by newer macs, that small tiny weird motherboard battery that's on powermacs and similar, I used alligator clips and ran the wires out the back to a AA holder that had enough Lithium Ion batteries to match the voltage, but in the Lisa's case, you'd want NiCADs.
Title: Re: I/O Card NICD Configuration
Post by: compu_85 on October 26, 2020, 11:18:23 am
Thanks! I'll probably mount a 4 cell holder in the system, and just remove the cells when it's not in use.