Williams Industries Inc., a Falls Church-based construction contractor, building materials manufacturer and construction equipment vendor, said it lost $80,838 in the third quarter ended April 30, compared with a loss of $633,650 a year earlier.

Revenue increased 16.1 percent, to $29.1 million from $25.1 million.

For the nine months ended April 30, Williams had a $920,653 profit (38 cents a share), compared with a loss of $233,406 a year earlier. Revenue in the nine-month period rose 21.8 percent, to $91.9 million from $75.5 million.

The company said its third-quarter performance improved because it was grappling with money-losing projects and trying to absorb newly acquired subsidiaries a year ago. Williams said it still lost money because of bad weather and project delays related to perceived credit problems in the real estate industry.

Schwartz Brothers Inc. of Lanham said rising sales of videocassettes, compact discs and tapes boosted its earnings 22.4 percent in the fiscal first quarter ended April 30 compared with the same period the previous year.

Profit for the first quarter was $131,012 (7 cents a share), on revenue of $29.9 million. For the quarter ended April 30, 1989, profit was $107,022 (6 cents) and revenue was $23.7 million.

Schwartz Brothers is an independent distributor of auto and video home entertainment products, such as videocassettes, audiocassettes and compact discs.

The company said sales have remained strong in the second quarter.

Sporting Life Inc., an Alexandria-based catalogue clothing retailer, said it lost $172,000 in its fiscal third quarter ended April 30, compared with a profit of $211,000 (21 cents a share) in the same period a year ago.

But revenue for the quarter rose 13 percent, to $3.7 million from $3.3 million in the third quarter a year ago.

For the first nine months, the Sporting Life lost $256,883, compared with a profit of $276,119 (27 cents) in the same period the year before.

Revenue was up 6 percent to $10.2 million for the nine months up from $9.6 million the year before.

Circuit City Stores Inc., the Richmond-based electronics retailer with several stores in the Washington area, reported a 12 percent increase in profit on a 21 percent rise in revenue for the fiscal first quarter ended May 31.

The company said it earned $12.1 million (26 cents) in the quarter, compared with $10.73 million (23 cents) in the first quarter a year ago. Revenue totaled $493.4 million, up from $408 million in the same period last year.

Officials said the firm opened three of its superstores, in Philadelphia, Orlando and Tampa, Fla., in the first quarter and closed a smaller outlet store in Los Angeles. The company also said it plans to establish its own credit card program in September.

Survival Technology Inc., the Bethesda-based company that makes medical devices and provides pharmaceutical and monitoring services for emergency medical care, said the growth of its commercial sales helped push its profits up 251 percent in the fiscal third quarter ended April 30.

For the first nine months of the fiscal year, its losses narrowed, Survival Technology said.

The company earned $250,400 (9 cents) in the third quarter, compared with $71,400 (3 cents) in the year-ago third quarter. Revenue rose 16.7 percent in the quarter, to $4.9 million from $4.2 million.

In the first nine months, Survival Technology lost $801,000, compared with a $1.3 million loss in the same period a year earlier. Its revenue rose 2.4 percent in the period, to $12.6 million from $12.3 million.

Much of the growth in its commercial business centered around the automatic devices people can use to give themselves injections, particularly a product that comes already filled with a medicine for allergic reactions.