From up-country Greenville, Maine, draftsman Mark Beckwith uses a computer to execute house-building plans for the Log Home Co. Nothing remarkable there -- except that Beckwith is a quadriplegic and can't manipulate a keyboard or a mouse. He draws arcs and angles by talking them into shape.

And at L.L. Bean in Freeport, Maine, employees incapacitated by repetitive-strain injuries continue to work by using PCs equipped with voice-response capabilities. The catalog outfitter didn't bother to perform a formal cost-justification study on the technology before adopting it. The company's premise: if it can keep a worker on the job, happy and productive, that's certainly better than having to pay workers' compensation.

As recently as three years ago voice-operated computer systems cost about $10,000. Today a basic system can be installed in a desktop computer for as little as $1,000. And businesses are installing them, spurred by the price plunge and by provisions of the Americans with Disabilities Act that call for alternative jobs for injured workers.

The product used by both Beckwith and L.L. Bean, DragonDictate Classic software, is marketed by Dragon Systems, based in Newton, Mass., and sells for $995. (You'll need to spend another $325 on a special signal-processor board for your PC.) This year Dragon has added the basic Starter Edition for $595, and the high-end Power Edition for $1,995. Among its customers: a modest-size law office, which invested in several systems that are primed to recognize and respond to a law-oriented vocabulary of words and phrases. Now the lawyers compose and print entire documents by dictating them to computers rather than to secretaries, cutting operational expenses in half.

A DragonDictate system converts every word it hears into text by piecing together the word's components and comparing the digitized combination with acoustic models in its built-in vocabulary. If the system is uncertain ( they're, their, or there?), it rolls a menu of best guesses onto the screen. And if none of those is right, the speaker "types" the word via either the international spoken alphabet -- alpha, bravo, charlie, and so forth -- or the traditional keyboard.

Because a given utterance can be used to represent any keyboard command -- ALT-F6, for instance -- the user can activate by voice such complex programs as Windows and Lotus 1-2-3. A lawyer could word process paragraphs of prestored boiler plate merely by pronouncing the word moot. And using his off-the-shelf drawing program, Beckwith spirits the cursor around by speaking strings of words such as, "Create line, up 10, space, draw circle." It's faster than using a mouse, he boasts.

DragonDictate products are available from Dragon Systems (617-965-5200). The recommended minimum requirements for the 5,000-word Starter Edition are an IBM-type PC with 12 megabytes of RAM, 29 megabytes of free hard-disk space, and a 486 microprocessor running at 33 megahertz.

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