Sustainer While Changing Batteries

it would be nice not to have to reboot every couple hours or so when I change out the batteries.
Gary Morrison wrote on :

A long time ago, I had a 16MHz 68030 PowerBook, with a very short battery life, so I had a lot of batteries. To make that situation more palatable, somebody sold a useful little gizmo: It was an adaptor that connected between a regular 9V battery and the AC-adaptor plug. You put the PowerBook to sleep, then this gizmo in where the AC-adaptor would go if you weren't "on the road," so to speak. You change the batteries out, remove the gizmo, and you can bring it back up from sleep.

Battery life is better on my 17" G4 critter, but I'll be taking a long airplane trip soon, and it would be nice not to have to reboot every couple hours or so when I change out the batteries.

Do any of you know of any gizmo of this sort for the 17" PowerBooks?

nospam replied on :

In article muaHe.87438$X76.29904@redacted.invalid, Gary Morrison mr88cet@redacted.invalid wrote:

A long time ago, I had a 16MHz 68030 PowerBook, with a very short battery life, so I had a lot of batteries. To make that situation more palatable, somebody sold a useful little gizmo: It was an adaptor that connected between a regular 9V battery and the AC-adaptor plug. You put the PowerBook to sleep, then this gizmo in where the AC-adaptor would go if you weren't "on the road," so to speak. You change the batteries out, remove the gizmo, and you can bring it back up from sleep.

Battery life is better on my 17" G4 critter, but I'll be taking a long airplane trip soon, and it would be nice not to have to reboot every couple hours or so when I change out the batteries.

Do any of you know of any gizmo of this sort for the 17" PowerBooks?

it is not needed - you can sleep and swap the battery in nearly every version of the powerbook, including the powerbook 17".

this gizmo was only needed for the first version of the powerbooks, the 100, 140 & 170. subsequent powerbooks had an internal battery to maintain it during sleep.

the ibook was the first apple laptop that lacked this battery, and later, the powerbook 12", which is essentially an ibook.

all other powerbooks, including the 17" can swap batteries during sleep.

Gary Morrison replied on :

it is not needed - you can sleep and swap the battery in nearly every version of the powerbook, including the powerbook 17".

Well now, that's strange: I coulda sworn I'd tried that before on this PowerBook, expecting it to behave as you described, only to see the sleep light flicker off immediately upon removing the battery.

However, I just now tried it and yes, it did indeed work. Perhaps something weird just happened to go wrong that one time I tried it, or maybe my 40-some-odd-year-old memory is what's "flickering off."

pailface88 replied on :

the ibook was the first apple laptop that lacked this battery, and later, the powerbook 12", which is essentially an ibook.

It should be noted that even though the ibook lacks a PRAM battery, it can still have the main battery swapped while in Sleep mode. It has a large value capacitor to do the same jop as a PRAM battery in this respect.

pailface88 replied on :

Gary, your PRAM battery can indeed be bad. They only last a few years. On some models they were a nicad or NiMH and on some models they were Li-Ion, all rechargable, but they do have a finite lifespan. On many of the older powerbooks the PRAM battery was supposed to be able to keep the computer RAM contents alive for 4 minutes while changing out the main battery. As the PRAM battery aged, this time would be reduced eventually to zero, while the PRAM battery still had enough capacity to actually keep PRAM contents alive while the computer was turned OFF (shut down) and while the AC power and main battery were both removed.

Therefore, just because your computer keeps its date and time when no AC or battery power is being supplied to it does not mean that your PRAM battery is good enough to keep the RAM alive while swapping out the main battery in Sleep mode.