Thanks to everyone for the interesting discussion on lead-acid batteries.
I seem to have gotten lucky with my new Portable. After two days of
charging at 300 mA, the Portable fires right up, and loads System 7.5 from
the 40 meg internal HD. The system also has the Apple 3 MB RAM expansion
installed, for a total of 4 MB RAM. No backlighting, though. The only side
effect of being long-dead seems to be a fairly fast drain on the battery
when the system is off and not plugged in to the adapter; I'll have to
experiment to see if this is due to the system going into sleep mode rather
than powering down completely, or whether the battery isn't holding it's
charge.
I'm still hunting for a Portable AC adapter and/or replacement battery
locally; if I can't find one, I may contact one of the list members who
indicated they may have one for sale or trade. Thanks to all.
Regards,
Mark Gregory