Apple Computer has significantly enhanced its Macintosh computer family with a new line that doubles as both portable laptop and desktop machine.
When traveling, Apple's PowerBook Duo is as light as any laptop while still offering a touch-typing-sized keyboard, a large-capacity hard disk drive and a bright, legible screen. The 4.2-pound machine can operate several hours on a battery charge, depending on usage.
In the office, plugged into an optional Duo Dock expansion unit, it becomes a no-compromise desktop computer with all the speed, expandability and connectivity of full-size Macintoshes.
Several manufacturers of IBM-compatible computers also offer laptop-docking station combinations, but Apple's design is particularly nice, making the transition from laptop to desktop, or vice-versa, quick, simple and almost foolproof.
As a laptop, the PowerBook Duo is superb if you can get along without a built-in floppy drive or a color screen. As a desktop machine, with a well-configured Duo Dock unit, it performs in the upper range of the Macintosh spectrum.
The great advantage is that you only have one computer, with a single set of programs and files. By buying one machine instead of two, you'll also save a lot of money.
Alternatively, you could buy the PowerBook 180 laptop ($4,469), which is as powerful as the PowerBook Duo 230 and includes a built-in floppy drive. With the PowerBook 180, you have the option of plugging in a color monitor and a full-size keyboard. Even so, you still won't have as much expansion ability as with the Duo units--and the PowerBook 180 weighs an additional 2.6 pounds.
The PowerBook Duo models are slightly smaller and lighter than other PowerBook models. The Duo 210 ($2,249) comes with a Motorola 68030 microprocessor running at 25 megahertz, four megabytes of operating memory and an 80-megabyte hard disk. The Duo 230 ($2,609 or $2,969) model runs at 33 megahertz and offers an 80- or 120-megabyte hard drive. Both have a crisp, bright screen displaying 16 shades of gray.
You can install an internal high-speed modem ($319), but if you need a floppy drive on the road, you'll need to buy an adapter and an external drive unit ($334).
At the office, you would install the Duo Dock unit, which measures about 12 by 16 inches and is about five inches high. When the PowerBook Duo is slipped into the Duo Dock, much like inserting a videotape into a VCR, the laptop powers the desktop system, with its microprocessor, memory and hard drive as the central components.
The $1,079 Duo Dock provides an internal floppy disk, two NuBus slots for expansion cards, room for an additional hard drive, and all of the normal desktop Macintosh connections, for color and gray scale monitors, standard or expanded keyboards, print, LocalTalk networking and SCSI devices such as CD-ROM, scanner and additional hard drives.
The PowerBook Duo 210 gives about the same performance as a desktop Macintosh IIci and a PowerBook 160. The PowerBook Duo 230 is comparable to a Macintosh IIvx and a PowerBook 180.
A PowerBook Duo 210, Duo Dock, Macintosh Color Display and a standard keyboard has a suggested price of $4,022. In comparison, a Macintosh IIci, Macintosh Color Display, a standard keyboard and a PowerBook 160 would total $6,202 suggested retail. It is proportionately more expensive to compare the more-powerful PowerBook Duo 230 with a Macintosh IIvx and PowerBook 180 combination.
After an initial glitch, the system I used worked well.
The Duo Dock won't latch onto the PowerBook Duo if you happen to have the security key turned to the locked position (which prevents a PowerBook from being removed once it is in place).
Apple's user manual lists the lock as something to check if you can't get the machines to mate. In fact, both the PowerBook and Duo Dock manuals tell users to be sure the key is in the unlocked horizontal position. Bad advice. The unlocked position of the key is vertical.
I felt fairly stupid discovering the proper key position only after returning the first Duo Dock to Apple because I thought it was broken. However, I did completely dismantle and reassemble the thing before returning it. It was well-constructed and fairly easy for a technically adept person to install expansion cards and another hard drive.
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