Discovery Could Greatly Expand Use of Single Line : Pacific Bell Triples Wire Capacity

In a bid to cash in on the lucrative merger of desk-top computers and telephones, Pacific Bell revealed Thursday that it has devised a way to increase more than threefold the amount of information a single telephone wire can carry.

Pacific Bell, the telephone service division of San Francisco-based Pacific Telesis, said the technology will enable a person simultaneously to handle two telephone conversations and transmit five sets of computer data from home or office. Existing technology permits one conversation and one set of computer data to be transmitted simultaneously over a phone line.

The company--which analysts agreed is among the leaders in the race to cram more information through the nation’s existing network of copper and fiber optic telephone lines--said it has applied for U.S. patents on the technology and will begin testing it in undisclosed areas of California on computer equipment supplied by Apple Computer Inc. of Cupertino.

No Details Given

Pacific Bell said the technology--which it refused to describe in detail--expands, at low cost, the ability of home or small-business computers to “talk” electronically with stockbrokers, travel agents, banks, department stores and a host of others offering services by computer.

The technology has the potential to hold down the cost of residential phone service by providing an important source of extra revenue for Pacific Bell through direct sales and licensing fees to other operating companies nationwide, said Robert B. Morris III, telecommunications analyst at Montgomery Securities Inc. in San Francisco.

It represents Pacific Bell’s hope of cashing in on the burgeoning, $1-billion market that is blending personal computers with telephones. The market is expected to grow “multifold” during the next decade, Morris said.

Apple said it believes that communication by computer will be “the driving force” in the personal computer market. An Apple spokesman said the company “will only provide computerized equipment for the project” and is “in no way involved in a joint venture or intending to be Pacific Bell’s equipment supplier in the commercial market.”

Method Appears Unique

New York-based ITT Corp. and Chicago-based Ameritech Corp. are among other companies testing ways to expand phone lines, but analysts said Pacific Bell’s technique appears to be unique in its combination of fitting more new channels into one line, working over existing phone wires and being compatible with a variety of telephone and computer equipment.

Thomas C. Edrington, assistant vice president of Pacific Bell, said the technology entails plugging a computer and a telephone into a small box installed in the home or office. He refused to give any other details about the technology.

Analysts theorized, however, that it is based on microchips--the miniaturized circuit boards that are etched on thumbnail pieces of silicon and tell computers what to do--and uses one of several techniques to eliminate the pauses between words or blanks between data during transmission.

Cuts Useless Data

This cuts the amount of useless data speeding through the wires, making room for more “useful information,” said Bradford Peery, an analyst with Hicks Peery, a San Francisco-based investment banking firm that specializes in telecommunications.

The new technology, for example, would allow an executive to hold a conference call with two others--or put one caller on hold--and send copies of a letter via computer to each caller.

Although Peery had not reviewed Pacific Bell’s announcement, he said any technology that expands the capacity of existing phone lines--most of which are the old-fashioned, copper kind--would be “truly significant” because it would eliminate the cost of installing new lines.

Pacific Bell said it will begin testing the technology in California communities “with high concentrations of residential homes and small businesses.” The company ruled out San Francisco and Los Angeles.