When you work on a portable computer, you can't expect all of the features that a desktop machine offers. To begin with, portables usually are slower and less powerful.
On top of that, their screens--generally liquid crystal displays similar to those on most electronic watches--can be tough to read.
Worst of all, however, many so-called portable computers aren't very portable. When I'm about to get on an airplane, the last thing I want is another 26 pounds of carry-on luggage. Some of the "portables" can barely fit under an airline seat.
There are some exceptions, however, and Radio Shack's Model 102 is one. This $499 machine weighs only three pounds and runs on four AA batteries.
The Model 102 comes with 24 kilobytes, or more than 24,000 characters, of memory. It is also equipped with a built-in 300-baud modem and software for word processing, communications, scheduling and programming in the BASIC language. The built-in software is rudimentary, but the word processor--which I'd consider its main function--is adequate for taking notes or writing short articles.
The machine has no disk drives--data is stored in its memory and stays there even when the power is turned off. Likewise, the software is permanently etched into the machine. Consequently, it is very simple to use.
The Model 102 is not compatible with the IBM PC or any other computer, but files can be transferred between it and other computers with a $30 cable available from Radio Shack. If your home or office computer has a modem, it's also possible to transfer data over a phone line.
My only complaint is with the screen. Its liquid crystal display is not nearly as readable as the cathode ray tube displays in desktop computers. What's more, the Model 102 displays only four lines by 40 columns, compared to the 25 lines by 80 columns on the IBM PC and most other computers.
All told, however, the Model 102's small size, light weight and simplicity make it an excellent choice for people who use computers on the run.
Other manufacturers have opted for making portables that provide nearly all the benefits of a desktop computer. For that you pay a price, however.
The Toshiba 3100/20, for example, is an IBM/AT compatible model with a 20-megabyte (more than 20 million characters) internal hard disk. Even the display, as portables go, is very readable. The bad news is that it lists for $4,700, weighs 15 pounds and does not run on batteries. I have access to one of these machines and find myself leaving it at home when I travel, particularly because I like to work on my computer when I'm aboard an airplane.
I had all but given up on a truly lightweight IBM compatible until trying Toshiba's new model, the T1000. It weighs less than 6 1/2 pounds and comes with a carrying case and a built-in handle. It is the first MS-DOS machine that easily fits in almost any briefcase. I recently took it on a trip and was truly impressed.
Unlike most portables, all of the standard MS-DOS operating system programs are built into the computer, so you don't have to waste space by copying the operating system on the one diskette.
Toshiba's optional memory board stays alive for 40 hours even with the unit unplugged and power turned off. As a result, it can be used to store programs, freeing even more space on your one diskette and speeding up access. When you're at your desk you can plug in an optional 5 1/2-inch floppy diskette drive for transferring files to a regular PC. You can also plug in an external monitor, should you get tired of looking at the built-in liquid crystal display.
At the suggested retail price of $1,199, I'm tempted to buy a T1000.
Besides weight and the quality of the displays, there often is another problem in working with IBM PC-compatible laptop computers: They typically use smaller disks than desktop machines. Consequently, sharing programs and data can be complicated.
In most cases, PC-compatible laptops work with the same sort of 3 1/2-inch diskettes used with the Apple Macintosh and IBM's new Personal System/2 machines. On the other hand, most standard IBM-compatible desktops use 5-inch floppy disks.
A variety of equipment is available to transfer programs and data between portable and desktop machines. To begin with, you can equip a PC with a 3 1/2-inch drive or buy a 5-inch drive for a portable. Or you can get Brooklyn Bridge, an ingenious product consisting of software and a cable linking the portable and the desktop machines. Brooklyn Bridge makes each machine operate as if it is a disk drive for the other computer. Thus, you can easily copy data or programs from one system to the other. The product is available for a suggested retail price of $129.95 from White Crane Systems of Atlanta, Ga. (404) 394-3119.
A new product known as DaynaFile enables an Apple Macintosh computer to transfer files back and forth between different size disks.
DaynaFile is a device that allows a Macintosh to read and write to IBM-compatible 5 1/2-inch and 3-inch diskettes. Its main purpose is to transfer files between the PC and the Mac, but the product can also be used to copy files between the two different IBM disk formats. In other words, this device can copy files from a PC to a Mac, a Mac to a PC or between the 3-inch and 5 1/2-inch disks used by the IBM PC and compatible computers.
The product is available with one or two drives and is priced from $595 to $849. Its versatility makes it a great deal for any business that uses both Macs and PCs, and its benefit for the owners of laptop computers is an added attraction. The DaynaFile is available from Dayna Communications, 50 South Main St., Salt Lake City, Utah 84144. (801 531-0600).