I
picked up a Mac Portable at a
thrift shop the other day. For those who aren't familiar with the
machine, it's basically a Mac
SE equivalent with a twice-as-fast (16 MHz) processor, in a
portable case.
Portable is, of course, a relative term. It was more portable
than a Mac II, but not much moreso
than an SE.
The greatest innovation of the Portable was probably the 8-10
hour lead-acid battery. While not exactly the smallest battery, the
Portable's long lasting battery meant that it could be used on the
road for a lot more hours than other laptop at the time.
The Portable also had a very sharp active matrix LCD screen -
much better than the SE's CRT or the screens in other laptops of
the time.
Unfortunately, the latest PowerBooks can just about manage 3
hours, and if you're actually doing something that uses the
processor's full capabilities or the hard drive, maybe you'll only
get two.
The Portable's fatal flaw was that you can't actually use the
computer without a somewhat charged battery in place. Although
there are tricks to get around this, I've had little success with
any of them. Thankfully this has not been an issue fo any later
Mac, and I can easily run my 12" PowerBook without it's battery if
I decide that I wante to.
This is especially valuable when the machine becomes so old that
it's not worth spending $60-70 for a new battery, yet the
computer's still perfectly useful as a (small) desktop.
There are ways to extend the battery life of a PowerBook - check
the "reduce processor speed" box, for example, in the Energy
preferences. On older Macs, there was the "spin down hard disk"
control strip module, which I find is unfortunately missing from
OS X in any form (I used to use it frequently if I was just
typing notes in class - why do I need the hard drive running?).
Turning down the screen brightness is probably the most obvious
trick to save battery life. Since the original Portable didn't have
a backlight, that might have been one of the keys to it's great
battery life. Another trick for older machines was to change the
screen bit depth to 256 or thousands of colours. While not exactly
practical on a PowerBook running OS X (OS X's interface
looks terrible with just 256 colours), it might help if you've got
an older machine.
Other popular things have been using two batteries. In Apple's
PowerBook 500-series, there were two slots for batteries, and these
machines could be ordered with both batteries if one wanted. These
"intelligent" batteries would report the actual battery status and
time remaining. That's not such a big deal now, but with the
100-series PowerBooks you had a rough indication of how much
battery power was left through a desk accessory, and that was about
it.
The G3 PowerBooks also would accept two batteries, one in place
of the CD-ROM drive. This could provide close to 6 hours of running
time.
With the G4s, however, the optional second battery was traded
for a smaller form-factor (the titanium models were advertised as
having a 5-hour battery, but it really lasted from 3-4).
Unfortunately, the battery life seems to be no better in the
aluminium models, and there's still no way to add a second
battery.
What I'd really like to see from Apple is a PowerBook that
allows for two batteries to be installed.
I love the size and form factor of the 12" PowerBook, however
the 3-hour battery life tends to be problematic. I often find
myself having to take the computer home to plug it in before my
next class, which isn't exactly convenient (I hate carrying the
charger with me). If I don't plug it in, the battery dies.
Adding a second battery to this machine might prove impractical,
if not impossible. The case is already extremely cramped - to the
point where the hard drive is so close to the aluminium casing that
it gets hot to the touch after running for a while.
In the future there will be technologies like fuel cells -
something that's starting to get more and more attention. But at
the moment we're stuck with the relatively old-fashioned LiIon
technology we're using. For the immediate future, the option of two
batteries in a pro-level PowerBook (especially a 17" model) should
be standard.
