In recent years fax-on-demand (FOD) has proved itself an effective business communicator. Software publishers use it to relieve overburdened tech-support staffs, and advertisers use it to answer product queries, sending back faxed descriptions as requested. But precomposed documents selected from a static menu may be things of the past. By adding the ability to send and receive raw data in real time, information dissemination by fax has taken a giant -- and inexpensive -- leap ahead. With interactive real-time FOD, a derivative of computer-to-computer electronic data interchange (EDI), an off-site caller with a fax machine can retrieve details from a business's database even while that database is in rapid flux.

As before, a fax's handset is used to dial, and the caller is answered by a recorded voice whose instructions lead to a given subject. ("Press 1 for product availability . . . ," and so forth.) But the requested information is read in real time directly from the host's computer file. A parts-distribution company could give its customers access to its inventory database, for example. Customers would query the database to determine up-to-the-second availability, receive a faxed-back answer, and then order those parts through the phone's keypad. Any orders of items would be written back to the database in real time as well, reducing the inventory count for the next caller.

In Dallas, FaxWare International is cashing in on the concept. The start-up's founder, Jeff Faith, operates applications that can be promoted to the public. A service already under way is a garage-sale locator, which Faith helped launch in response to Dallas's ban on posted handbills. And, tired of passing out rain checks for out-of-stock sale items, supermarket chain Kroger Stores is consulting locally with Faith about a real-time FOD application to shrink the gap between print-ad expectations and day-of-sale supply. When keeping automated track of fluctuating data for customers and vendors -- a progress report of a work order, for example -- "a business saves an immense amount of time by not having someone answer the phone," Faith says.

Faith shopped among dedicated products costing upwards of $100,000 but ultimately went for FaxBase System III, made by Fax on Demand, in Addison, Tex., when it was introduced this spring at a starting price of $5,995. (The price includes a PC as well as four voice channels and one fax channel; adding more fax channels runs about $500 extra per channel.)

But why would a business seeking raw data resort to a fax instead of a computer link? Because, says Faith, "making a phone call is not nearly so big a deal."

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FaxBase System III runs on IBM-type PCs and supports popular formats such as dBase, Paradox, Access, FoxPro, and SQL. A 486 PC with 80 megabytes of hard-drive storage can handle 36 callers at a time. Installations are modular and customizable. A business could, for example, tie real-time data into precomposed documents. For details, call Fax on Demand at 800-FAX-1777.

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