PowerBook 100: How Sony Perfectly Miniaturized the 16 Pound Macintosh Portable

You may have heard the original iBook called an iMac to go. The PowerBook 100 is a Macintosh Portable to go.

This week I'm going to talk about my first PowerBook - and one of the first PowerBooks ever. The machine is the PowerBook 100.

Some people think the PowerBook 100 was the first PowerBook, but it was launched in 1991 as the low-end model with the midrange PowerBook 140 and the high-end PowerBook 170.

The story is that Apple wasn't happy with the 15.8 lb. Macintosh Portable and gave Sony the task of miniaturizing it. Sony's engineers and designers came up with the PowerBook 100.

The Mac Portable and PowerBook 100.

Hardware wise, it was nearly identical to the Macintosh Portable. Both share a 16 MHz 68000 (the fastest 68000 Apple ever shipped), both had a 40 MB hard drive, both max out at 8 MB of RAM (well, the backlight model of the Macintosh Portable does), both have a 640 x 400 black and white (no shades of gray) screen, and both shipped with a 1.44 MB floppy drive.

But one thing is different: The 5.1 lb. PowerBook 100 is over 10 pounds lighter!

I bought my PowerBook 100 some time in 2005. I think I paid $30 for it. Unfortunately, when I got it it had a school name engraved into it, and the floppy drive did as well (but from a different school).

It was also missing the port cover (quite common for most 1xx series books), and one of the fold-out feet was missing, which is a shame, as the ones on the PowerBook 100 differ from the rest of the 1xx series (when you fold them out, they also push out about a quarter of an inch). Quite clever, but this also meant abandoning the "screwed down from the inside" solution, and they are merely popped on a hub.

My machine had the stock 2 MB of RAM, which I soon maxed out to 8 MB with a 6 MB RAM card.

I am lucky: The school had sprung for the 40 MB hard drive option (the budget config had a 20 MB drive). It is starting to show it's age, and is quite loud.

My machine is running System 7.1 - and runs it quite well. I have mine set up with a bunch of games, and an old version of Microsoft Word (4.00b) and Excel.

It's nice and fast, but there are a few other issues with it: There's a splotch on the screen, which I can minimize by adjusting the contrast and brightness (which are wheels instead of sliders, which are used on the rest of the 1xx series). Another issue is when using the external floppy drive, I get some rasters on the screen whenever it's reading and writing to the disk, but my guess is that is just the draw of the power of the floppy drive. It might not have been noticeable when the machine was new, but I can see it now.

The PowerBook 100 is the oddball off the 1xx series for many reasons. The external floppy, the smaller screen (which absolutely cute with the shape of the bezel), the physically and chemically different battery (a flat, elongated lead-acid thing), and one thing most people don't think about: It's easy to work inside. Just unscrew the screws on the bottom, open up the machine, push the screen flat, and lift up the keyboard.

The screen and speaker attach to the machine by a single cable to the motherboard, not a complex and hard to find daughterboard like the rest of the 1xx series. I can rip this machine apart in under 15 minutes, which is something unmatched in today's complex portables.

Another thing I love is the floppy drive, which was repurposed for the PowerBook Duos. It has a short cable, but the plug is huge. It is about 2" - not the cable, just the part that plugs into the computer. It uses a custom HDI-20 port, which is like a shrunken HDI-30 port. It also has a spring loaded release.

But the part that is real money is the foot (yes, I have a foot fetish, but only on Macs). It acts like a cover and folds over the front of the drive, and it flips down to raise the drive up when it's in use. There is also not a whole lot of casing to the drive, so it's relatively small. The only issue I have is finding enough clearance behind the computer to use the plug.

Other little things I love: The backup batteries are three easy to find CR2430 button cell batteries that go in a little swing out door on the back (quite clever, as most other 'Books require you to rip the machine down to the chassis just to get to it; I'm looking at you, WallStreet).

The interrupt and reset switches are also easy to reach and press buttons on the side - no flip down of the port door or need for a paper clip (also a popular iPhone repair tool) required.

There is no power key, which some people might find weird, but I don't. You press any key on the keyboard, and it chimes to life. I use the spacebar, and it feel like I'm waking the machine up, not turning it on. I also like the smaller trackball, which fits nicely in my hand - a lot easier than the ones on the rest of the 1xx series.

All in all, the PowerBook 100 is a great little 'Book. If you can find one, snatch it up. It's very light, and if you're lucky enough to have one with a working battery (mine is dead, but I have an external one), these make great little creative writing machines. Just make sure you have a quiet hard drive, or spin it down, or make a RAM disk and run off, and you can go for hours.

I would not relate the PowerBook 100 to rest of the PowerBook 1xx series, since it's such an oddball. It's more closely related to the PowerBook Duo series, and I guess in some ways it was a precursor of things to come in 1992.

The photos that accompany this article are of Macs at Low End Mac headquarters; they are not of Leo's PowerBook 100. As you may notice in the photos, ours is missing a battery.

Further Reading

• The Wonderful PowerBook 100, Heather Anne Hurd, 2000.12.11
• Hands On: PowerBook 100, Dan Knight, 2001.03.21
• The Great Old PowerBook 100 and the Death of the PowerBook Name, Joe Rivera, 2006.03.07
• Field Testing the Carpenter's PB 100 Fix, Manuel Mejia Jr, 2000.05.09
• Macintosh PowerBook 100, author identified as "pb5300". "Until the release of the 100, both Mac and PC portables were heavy, bulky affairs and were not really any more portable than a Mac SE, Plus or Classic."
• PowerBook 100 FAQ
• PowerBook 100, Wikipedia