Halifax Engineering Inc. of Alexandria had a profit of $233,000 (20 cents per share) in the quarter ended Dec. 31, compared with a $575,000 loss in the same quarter a year earlier.

Halifax is an electronic services and facilities support company with government and private contracts. The company pointed out that its loss in last year's quarter was due to one-time costs for legal expenses and said that the other major reason its earnings improved was growth in its electronics division.

In the quarter, the third of its fiscal year, Halifax's revenue rose 10 percent to $7.4 million from $6.7 million a year earlier.

In the first nine months of its year, net income at Halifax rose to $1.3 million (66 cents), compared with a loss of $340,000. Revenue rose 6 percent to $22.4 million from $21.2 million.

Comnet Corp. of Greenbelt said its profit rose 56 percent in the quarter ended Dec. 31 compared with the same quarter a year earlier.

The computer services company said its net income for the quarter, the third of its fiscal year, was $361,000 (13 cents per share), compared with $231,000 (9 cents) a year earlier. Revenue rose 56 percent to $7.5 million from $4.8 million.

The bulk of Comnet's revenue comes from its 83 percent ownership of Group 1 Software Inc., a Greenbelt company that sells software to manage mass-mailings. Group 1 had record high revenue and profit in the quarter.

In the first nine months of its year, net income at Comnet rose 48 percent to $1.1 million (39 cents) from $744,000 (28 cents). Revenue rose 24 percent to $19.4 million from $15.7 million.