Dynalectron Corp., which frequently has depressed first quarter profits of winter weather, reported it made a $201,000 profit (3 cents a share) in the 1979 period, against a $420,000 (7 cents) loss a year ago.

Another McLean company, Flow General Inc., reported a sharp increase in earnings but profits were off at Washington Gas Light Co.

Dynalectron credited its turnaround to ahead-of-schedule work on several large construction projects, better-than-usual business in its aircraft services division and the improving strength of the dollar.

A year ago Dynalectron reported it lost $154,000 in the first quarter translating foreign business into dollars, but this year the company said it had a "nominal gain" on currency transactions.

The company's revenues for the three months ended March 29 increased to $75.2 million from $66.9 million the same period of a year ago.

Dynalectron said its backlog of orders has increased to $239 million from $224 million.

Flow General's earnings were up 43 percent for the three months ended March 31 and up 48 percent for the first nine months of its fiscal year, the diversified technology company reported.

For the quarter Flow General earned $593,000 (36 cents per share) on revenues of $15.8 million, com See PROFITS, D12 Col. 1 PROFITS, From D8 pared with profits of $414,000 (28 percents) on revenues of $12.6 million a year ago.

The nine months earnings were $1.6 million (99 cents) compared with $1.09 million (72 cents) and sales increased to $43.1 million from $35.5 million.

The gains in earnings per share were less than the overall profit increases because the company had about 10 percent more stock outstanding this year.

Washington Gas Light Co. reported its earnings for the first three months of the year fell by nearly $4 million compared with 1978, but because of a change in accounting methods, the company reported a $1.7 million impovement in net earning income.

Net for the quarter was $20.9 million ($.63 per share) compared with $19.2 million ($4.25) in 1978. But the 1979 figures include $4.4 million 1.01) resulting from reporting revenues on gas delivered to customers but not yet billed. Without that change earnings would have fallen to $16.5 million ($3.62) for the three months.

For the 12 months ended March 318 Washington Gas earned $12.6 million ($2.90) compared with $12.8 million ($2.95).