McGraw-Hill's Housing magazine has been purchased by Hanley-Wood Inc., a local company that also publishes Builder magazine, the official publication of the National Association of Home Builders.

Hanley-Wood said Builder magazine will absorb Housing's editorial features and expand its coverage of economic news.

The company also publishes the American Institute of Architects Journal.

Housing, a 30-year-old magazine formerly owned by Time Inc., will publish its final issue in October.

Computer Entry Systems of Silver Spring said it has completed its merger of Amer-O-Matic Corp. into a CES subsidiary.

CES manufactures optical character-reading equipment, and AOM had been considered its major competitor as a leading supplier of remittance-processing systems to the financial industry and the government. The two firms are about the same size. Revenues were $7.8 million last year for CES and $7.6 million for AOM.

Dividends: American Security Corp. declared a quarterly dividend of 32 1/2 cents per share, payable Oct. 15 to stockholders of record Oct. 1. . . .Fair Lanes Inc. declared a dividend of 10 cents per share and a 5-for-4 stock split in the form of a stock dividend distribution. Both are payable Nov. 15 to shareholders of record Oct. 25. . . .Woodward & Lothrop declared a dividend of 42 1/2 cents per share, payable Dec. 1 to stockholders of record Nov. 12. . . .Bank of Maryland of Hillcrest Heights declared a dividend of 15 cents per share, payable Sept. 30 to shareholders of record Aug. 31.

Maryland National Bank has opened an office on New Hampshire Avenue in Langley Park.

George Washington University law school has a "small business clinic" that offers free legal advice to residents of D.C., Maryland and Virginia who already own or are planning to start a small business, partnership or nonprofit organization.

Dynalectron Corp. has approved the purchase of up to one million shares of its common stock on the open market or through privately negotiated transactions. The repurchase program is scheduled to begin no sooner than ten days after public announcement of the company's third quarter earnings. The shares represent about 11.6 percent of Dynalectron's 8.6 million shares outstanding and may be used for debenture conversions, acquisitions, stock option plans and other general corporate purposes, the company said.

McLean Safe Deposit Center Inc., a business offering safe deposit boxes for rent, will hold its grand opening tomorrow at 6862 Elm St.

McLachlen National Bank has opened new branch offices in the Friendship Heights and Dupont Circle neighborhoods.

Ursell's, a Georgetown furniture store, has merged its operations with Kramer & Scott, a furniture store on Kensington's "antique row." The owners of Ursell's will retire, and Kramer & Scott will move some of its inventory into the space at 3243 Q St. NW.

Bank of Bethesda plans to open its first "mini-branch" in December. The bank will be adjacent to the pedestrian walkway being built over Rte. 355 from the planned Metro station to the Rockville courthouse.

United Virginia Bank has announced a proposed public offering of $80 million principal amount of zero coupon certificates of deposit. The certificates will have a face value of $1,000. Buyers will have the option of purchasing them at $500 or $400, with maturities of about six and eight years, respectively.

On Line Computer Center, the personal computer store franchise of On Line Microcenters Inc., has opened in the Pan Am Center in Fairfax.

Stern Office Furniture Inc. has formed a wholesale office furniture division called ASI, or All Sources Instock. It will serve Washington, Baltimore and Philadelphia.