To Gerry Udwin, newly named Washington office chief of Westinghouse Electric Corp.'s broadcasting and cable TV subsidiary, good business can also mean "good works."

The veteran TV and radio newsman says "Group W," as the New York-based unit is known, is proving that "public service programming" can be profitable and well worth the investment of one of the country's largest broadcasting and cable companies.

Group W, producer of TV ("PM Magazine") and cable ("Home Team Sports") programming, has demonstrated this with the success of an educational program called "For Kids Sake," Udwin said. The program, which was conceived by the company's network-affiliated station in Boston, WBZ-TV, has been nurtured by Group W into a national public service program with plenty of sponsors.

The program's success, said Udwin, is based on a simple economics of scale; a large company like Group W can better afford to produce public service programming than a local station and can turn around and market it on a national scale.

Udwin's promotion to head of Washington operations for Group W, succeeding Wallace Dunlap, who is retiring on June 30, will mean greater responsibility for helping to develop public service programming.

But perhaps more importantly, he said, as Washington representative, his new job will be to "flak" Group W's "good works," as well as lobby Congress, the White House and industry representatives for policies that are conducive to more public service programming.

Of the myriad communications specialties Group W has developed, from owning major-market TV and radio stations to producing TV programs, public service programming has become a personal cause for Udwin because of his background in news and public affairs.

In 25 years of working for Group W, Udwin has spent 21 reporting the news. Starting out with a Chicago radio station in 1961, he moved to the Washington news bureau in 1967, covering Congress and the White House. He was bureau chief from 1977 until 1982, when he became a vice president and took an interest in public service projects. BANKING, FINANCIAL SERVICES

Barbara D. Blum, president and chief executive officer of The Women's National Bank, has been elected chairwoman of the board for the bank and its holding company, 1st WNB Corp. Blum, who led a small group of investors in acquiring the bank last year, succeeds Kerry H. Stowell, who resigned from the position two weeks ago because the bank was unable to obtain adequate insurance to protect directors and owners from lawsuits. In addition, the bank announced the appointment of three new board members: Peter C. Linzmeyer, a partner in the law firm of Foley and Lardner; Marie Ridder, a journalist and public official under the Johnson administration, and David E. Weisman, a partner in the law firm of Meyer, Faller, Weisman & Greenburg.

Citizens Bank & Trust Co. of Maryland, which in November was the target of an employment discrimination suit by the Equal Employment Opportunity Commission, has appointed James R. Fridie as the first minority member to sit on the Riverdale bank's board of directors. A bank spokesman said the bank had been "actively looking for a qualified minority to come onto the board" since the recent death of Philip Lustine, the owner of a car dealership. Fridie, an information analyst and biochemist, has more than 40 years of experience as a research and management consultant, including work at Sloan Kettering Institute for Cancer and Allied Diseases in New York and Walter Reed Army Hospital. The bank has denied the charges in the EEOC lawsuit, which is still in litigation.

Sovran Bank has promoted Christopher A. Brigham to first vice president in the real estate finance division in Arlington. Also, Judith L. Cortese has been elected an auditing officer and Joan M. Allen has been named retail banking officer.

Thomas G. Moore, president and chief executive officer of the Central National Bank of Maryland in Silver Spring, which recently was acquired by Citizens Bank and Trust Co., will become president and chief executive officer of Farmers National Bank of Maryland, the Annapolis company announced. Charles L. Schelberg will remain chairman of the bank and chairman and president of Farmers National Bancorp, the bank's parent company.

Directors of the Acacia Group, an insurance and financial services company, have announced the following promotions: Haluk Ariturk, to vice president and actuary; Lavonne Asher, vice president and controller; John Pluhowski and Sam Benedetti, second vice presidents; Lisa Andrews, associate counsel, and Linda Friedlander and Betty Matney, managers.

George M. Brady Jr., chairman and chief executive officer of the National Corporation for Housing Partnerships, has been elected director of First American Bank.

Federal Realty Investment Trust has promoted Meredith A. Olson to senior vice president for acquisitions of the Chevy Chase owner of 27 shopping centers. She was formerly vice president. INDUSTRIAL, MANUFACTURING

General Motors Corp. has announced changes in its public relations staff in Washington: R. T. Kingman, former director of the office who has been on medical leave, will serve on special assignment to the company's director of news relations. John J. Hartnett, manager of news relations, will become director of the Washington office. William H. Noack, formerly with GM in Europe, will succeed Hartnett. PROFESSIONAL SERVICES

C. Joseph Stetler, former president of the Pharmaceutical Manufacturers Association, will become of counsel to the Washington office of Royer, Shacknai & Mehle, a law firm that specializes in health-related law and finance.

Robert P. Davis, previously chief of staff to Transportation Secretary Elizabeth Hanford Dole, has become a partner in the law firm of Anderson, Hibey, Nauheim & Blair.

General Maintenance Service Co., a building maintenance contractor and one of Washington's largest private employers, has promoted Ron Neilson to director of marketing and Victor Santos to regional manager for the Northern Virginia area.

Martin E. Crahan, former director of development adminstration for Prince William County, has joined the architectural firm of Dewberry & Davis as branch manager for the firm's new Manassas office. He will coordinate all planning and development projects in the county.

AEPA Architects Engineers has named Mauro E. Mujica vice president of architecture. He was formerly a partner in the investment banking and real estate firm of Mujica and Berlin.

Keyes Condon Florance Architects have promoted three associate partners in the firm to principals: Thomas N. Eichbaum, Philip A. Esocoff and Tam D. Nguyen.

Cort Furniture Rental, a national home and office-furniture rental firm, has appointed Lori Vise national marketing manager for the Fairfax firm. She was previously a consultant with Michael M. Kaiser Associates in Arlington. In addition, Michael Connors, a former real estate analyst for Mobil Oil Corp., has been named manager of facilities.

Software AG Systems Inc. has appointed Bruce R. Mancinelli, formerly of Applied Data Research, to vice president for market development at the Reston software developer. COMMUNICATIONS

American Telephone and Telegraph has named Gary J. Reichow eastern regional vice president for AT&T Network Systems in Bethesda. He replaces Peter D. Fenner, who became vice president with AT&T Network Systems Product Management and International Strategic Development.

Frank Martineau, president of the Martineau Corp. and editor and publisher of Association Trends magazine, has been named chairman of the publishing company. Jill Martineau Cornish, formerly vice president for administration, will succeed Martineau as president and publisher. Kathleen Hemming, editorial and production manager, will become editor of the weekly journal.

Interface Video Systems, a postproduction video company in Washington, has promoted Jane E. Hurst to the post of operations manager from production manager.

MCI Communications Corp. has elected Dean R. McKay, a member of the IBM advisory board and former director of IBM, to the company's board of directors, bringing membership to 14.

Frank Heneghan, sales manager of McArdle Printing Co., has been appointed vice president for sales of the Silver Spring newsletter and magazine printing firm. HOTELS, FOOD SERVICES

The Vista International Hotel, located at 1400 M St., has appointed Rex Rice general manager. He is the former general manager of the new Hilton International Windsor.

The Grand Hyatt Washington has promoted Chris Jones, formerly of the Hyatt Regency Memphis, to sales manager.