They didn't call it Ma Bell for nothing: In the old days, working for the telephone company was considered to be as safe as working for your own family.

"The Bell System was a close-knit group," according to Bob Belanger, president of the Local 2108 chapter of the Communications Workers of America. "You'd never get rich, but you'd never starve, either. And if nothing else, you had security."

But that was before a federal court tolled the Bell for divestiture and ordained an era of competitive communications. Since Aug. 21, when AT&T officials announced that the Information Systems group, a division responsible for office computer systems, would pare 24,000 jobs from its 117,000 jobs nationwide, approximately 200 employes of the company's Beltsville operation have been swallowing fear with their coffee.

"I remember what my old boss said the day I was hired," said 34-year veteran John Ryan, a service technician at AT&T Information Systems in Beltsville. "He said, 'Do your work, keep your nose clean . . . and you'll have something to retire on and be comfortable in your last years.' "

Now, said Ryan, raising his glass: "I hope he's turning over in his grave."

Although company officials said no announcements about the reductions will be made until next week, the Beltsville office is buzzing with reports from the national AT&T grapevine that the operation will be moved to New Jersey and its employes either asked to relocate or be laid off. Another 200 workers connected to the regional training office and certain field services are said not to be affected.

AT&T executives will not confirm the closing, but workers at the Beltsville office said that they already are starting to worry about their future, because some of their clients have heard the report, their colleagues in other cities have heard it and their managers and union representatives have heard it.

And the more they hear, the worse it sounds.

"There are rumors they're going to lay off . . . more people over the next three years," Belanger said. "What good does it do these people to pick up and move to New Jersey, if they're just going to get laid off again next year?"

"I've been gritting my teeth so hard I cracked a crown," Ryan said. "My dentist made me a plastic guard to wear at night, and I bit it in half.

"It's been so bad around here that I already had my retirement papers in," Ryan went on. "Then my wife had something like a stroke; it's either 'Bell's palsy' or muscular dystrophy. I told her I had to have a reason to get up and go to work every day, so we sold our house and bought another so I'd have a house payment again. A mortgage is a powerful motivator."

"I'm not moving," Charlie McLaughlin said flatly. "I'm sick of being juggled around, and if it means going on unemployment, that's what I'll do.

"They came in here after the layoffs in December and said, 'You have absolutely nothing to worry about. This center is critical to our government customers, it'll be here forever.' And so my wife and I went out in February and bought a house.

"I've been through this routine before," McLaughlin continued. "After 12 years in Philadelphia, they sat me down and convinced me to move to Denver or I'd lose my job. It took me five years to get out of there, and I had to move back at my own expense."

Ryan and McLaughlin said they know of only one technician who is willing to accept a job in New Jersey if one is offered: a man with five children whose youngest child needs a liver transplant and for whom uninterrupted medical coverage is essential.

The Beltsville operation, known as the Capitol CSSO (Customer Services Support Operations), handles data systems for a large number of federal agencies in the Washington area, including House and Senate offices; the FBI; State, Treasury and Agriculture departments; Fort Meade; the Navy Yard; the Marine barracks and the National Aeronautics and Space Administration.

While nearly half the reported problems can be corrected long-distance through remote computer hookups, two of the sales pitches have been the group's close location and its assignment of a specific service technician to each account.

"AT&T sold this company on the basis of personalized service," Ryan stormed. "They'd bring these people out to meet us, we'd . . . flirt with 'em or whatever it took to get the account. They sold us, and now the closest representative is going to be in New Jersey."

AT&T spokesman Al Wann, emphasizing that no official decision concerning the Capitol CSSO has been announced, said some employes might be offered positions with other AT&T divisons, and that AT&T probably would help set up a pool for laid-off employes.

"I've had inquiries from three other companies already -- I think one was a recruiting firm -- about a pool," Wann said. "Besides, technical skill has a high market value."

But Belanger said that more than half the employes at the Beltsville office are clerical workers and support staff. They are predominantly women commuting from the District and are less likely to be able to uproot their families for a move, he said.

"There are a lot of single parents in there, and wives whose second income is a necessity of life . . . and women who couldn't find a job in the city," Belanger said. "What's their market value?"

According to sources within the company, only two of the approximately 40 managers and supervisors will be offered places in New Jersey; the rest will be "terminated" on Oct. 31.

"I've had one supervisor on the phone for the last 30 minutes, in tears over her lack of job security," Belanger said. "But she's afraid to say anything: They're all hoping to be one of the two."

The union's contract with AT&T provides some early retirement or supplemental pensions, depending on length of service, for employes whose jobs are declared surplus. But an employe who declines a position with the company in another city may receive only minimal benefits -- as little as one week's paycheck for an employe with only a year's tenure.

Even the most skilled employes fear that they may have trouble finding new positions.

"Now that [the telephone company] split, C&P won't take anyone back," Belanger said.

These are dismal days for the union. While the national CWA is losing ground to the newer, nonunion telecommunications firms, Local 2108 is reeling from the one-two punch of attrition and technology. As traditional jobs are elimimated, the union has been trying to help its members retrain for new careers, thus acknowledging its increasing obsolescence.

In the next five years, Belanger predicted, Local 2108 probably will shrink from 3,500 members to 2,500 or fewer. "With electronic switching, what used to take 10 trained technicians 40 hours a week to do is now done by one guy in about four hours a week," Belanger said. "Four hundred hours to four: They're computerizing us right out of the business."