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High speed modems (at 2400 baud)

technofile  by al fasoldt

Columns and commentaries in a life-long dance with technology
 

Simple gray rule


Flashback: High speed modems (2400 baud) become affordable
 

By Al Fasoldt

Copyright © 1987, The Syracuse Newspapers

How right can can one person be while being wrong at the same time? Read this and see for yourself. It's from 1987.

A mile marker in the evolution of modern telecommunications was reached in June, unheralded and almost unnoticed even by computer professionals. For the first time, the retail price of a high-speed modem—the device that allows computers to communicate over ordinary telephone lines—has dropped to $100.

A manufacturer in Chicago has pegged that price on one of its models, and other companies will match it soon. By the end of the summer, competition among discounters is certain to knock prices down into the $90 range or even lower.

Like most other consumer electronics products, modems have become cheaper year by year. But the drop in the retail cost of the high-speed versions has happened much faster than many industry insiders had predicted. Two years ago, these modems sold for at least $500, and last year the cheapest models listed for $200.

The price reductions are impressive, but the real significance lies in the technololgy that has made it possible. Integrated circuit chips incorporating all the electronic elements of a modem are now being produced in huge quantities for these high-speed modems, which operate at a transmission speed of 2400 baud (about 240 characters per second).

The same design principles that pioneered the manufacture of single-chip 2400-baud modems are now being applied to the next level of computer communications, 9600-baud modems. These super-speed modems sell now for at least $900, but they won't stay that expensive for long. Industry analysts say that 9600-baud modems may be selling at retail for $500 within six months to a year.

Modems are the essential link between computers worldwide. A computer equipped with a modem can share information with any other computer as long as it, too, has a modem. Modems can be separate devices, usually the size of a hardcover book, or they can be fastened inside the computer's case. A dialing circuit is built into the modem, and it calls the other computer and sets itself up to send or receive data.

Modems make computer bulletin boards and nationwide computer information services possible. They also allow banks to share account records among their branches, and make it easy for businesses of all kinds to gain access to financial and inventory data.

Modems also are used when computers communicate by methods other than telephone lines, such as in ham radio data transfer and in satellite links between computers that are thousands of miles apart.

Modems work by sending and receiving tones at different pitches. High-speed modems alter the tones in other ways, also. Coded within the warbling tones are numbers that have been broken down into their essential parts. Both standard computer data and letters of the alphabet are represented the same way.

Transmission speeds, called baud rates in honor of the French inventor J.M.E. Baudot, were limited to 300 baud until about seven years ago, when the Hayes company introduced a 1200-baud modem. At 300 baud, text that is being transferred is usually easy to follow, but most people have trouble reading at 1200 baud because the words scroll across the screen too quickly to follow.

Because of the poor quality of most of the telephone lines in North America at that time, 1200 baud was considered the highest possible transmission speed that computers could use over standard, "dial-up" lines.

Research into ways of packing more information into the tone patterns of modems led to 2400-baud versions about four years ago. This rate was then considered the new limit, although it was achieved at such an expense—$1,000 or more for most of the first 2400-baud modems—that consumers had little chance of moving up to the faster speed.

They had little incentive, too. Information services such as Compuserve could not operate at 2400 baud and only a few hobbyist bulletin boards upgraded their modems to the faster speed.

That has changed drastically today. Most nationwide information networks have switched to 2400 baud as an optional third baud rate, and thousands of bulletin boards offer all three rates, too. (Modems sold as 2400-baud units usually can be switched to 300 baud, and all of them can operate at 1200 baud also.)

The pace of change is being accelerated by more than technological improvements. Consumer expectations are rising, too, fueled by the realization that high-speed communications are at last within easy reach. While 1200 baud was satisfactory for years, as soon as 2400-baud modems appeared many computer users discovered that the higher rate made computer calls much faster—and, in long-distance use, a lot cheaper, too.

The same phenomenon is beginning to show up in a heightened interest in 9600 baud. Where will it end? Some experts say 9600 is the highest baud rate that even good quality phone lines can support. But the researchers who pushed the highest baud rates from 300 to 1200 and then to 2400 and now to 9600 know that the experts were wrong before, and even now some of them are talking of 38,400-baud modems within a decade.

That would be a speed of nearly 4,000 characters a second. Not even Evelyn Wood could keep up with that.


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