B.F. Saul Real Estate Investment Trust reported a loss of $4.4 million (71 cents a share) for the year ended Sept. 30, after earning a profit of $3 million (50 cents) the previous year. A headline in Thursday's editions of The Washington Post incorrectly reported earnings of the Bethesda realty trust. Executives of the Saul REIT said the loss resulted from a dramatic plunge in condominium sales caused by high interest rates and the poor economy. A year earlier, the trust earned $11.6 million on condo sales, but last year's condo profits amounted to $417,000.

B.F. Saul Real Estate Investment Trust yesterday reported a loss of $328,000 in the fourth quarter against a loss of $1.9 million last year. Revenues increased to $18.8 million from $16.4 million.

For the year, B.F. Saul's revenues dropped to $61.9 million from $82.3 million. It lost $4.4 million from earnings of $3 million in 1981.

Hadron Inc., a computer software, lasers and direct-mail company in Vienna, said it earned a profit in its second fiscal quarter and first half after losses a year ago.

Gary A. Prince, controller of the firm, said the restatement of results to acknowledge the acquisition of Sincon earlier this year had created the year-ago loss.

In the three months ended Sept. 30, Hadron said it earned $188,000 (2 cents a share) compared with a $150,000 loss a year ago. Revenues rose to $6.6 million from $4.1 million. Income for the first half of the year was $4,000 compared with a $189,000 loss a year ago, with revenues growing to $13.6 million from $8.3 million.

BTR Realty Inc. of Baltimore said the slowdown in the commercial and residential real estate markets led to a decline in earnings the third quarter and first nine months of the year. The company, which owns and operates shopping centers and other commercial property and owns a variety of undeveloped commercial and residential land, said it earned $186,522 (17 cents a share) in the third quarter, compared with income of $323,550 (29 cents) last year. Revenues fell to $3.2 million from $3.8 million in the quarter.

BTR said that its nine-month earnings were $700,759 (64 cents), down from $794,595 (72 cents) last year. Revenues fell to $7.6 million from $11.5 million in the period.

Riviere Realty Trust of Washington reported that third-quarter profits doubled to $148,087 (16 cents a share) from $74,664 (10 cents) for the same period last year. Nine-month profits increased to $262,736 (29 cents) from $226,255 (29 cents) during the same period in 1981. Funds from operations and capital gains were $320,404 in the latest quarter, up from $239,924 last year; and, for the year to date, $770,247, up from $699,936.

Federal Realty Investment Trust recorded third-quarter profits that were slightly higher than a year ago, although the Chevy Chase company's nine-month profits dropped. Its latest quarterly profits were $569,000 (14 cents a share) compared with $551,000 (14 cents) for the same period last year. Nine-month profits, however, declined by 4 percent to $1.97 million (48 cents) from $2.065 million (52 cents).

Third-quarter revenues increased from $3.53 million to $3.56 million; revenues for the nine months, from $10.6 million to $11.2 million.

Another area firm, Tech Serv Inc. of Beltsville reported a loss of $86,320 for the its quarter ending Sept. 30. The company lost $63,077 for the same quarter last year. Tech Serv, which makes radio-controlled aerial target systems, blamed its losses on delays in the award of government contracts. Revenues were down to $518,022 from $536,324.

MIW Investors of Washington, owner of shopping centers and a mortgage lender, reported net income of $804,451 (21 cents a share) in the first half compared with $199,977 (5 cents) last year. Gross revenues climbed to $1.4 million from $976,066.

In the latest quarter, MIW, which has headquarters in Bethesda, had profits of $673,830 (18 cents), a dramatic improvement from last year's $45,727 (one cent). Gross revenues increased to $752,630 from $546,722.