Dirgham Salahi, the chief witness against Alexandria Commonwealth's Attorney William L. Cowhig, testified yesterday that he paid the prosecutor $500 a week for 64 weeks because Cowhig threatened to close down Salahi's lucrative bingo games.

Salahi, director of the Montessori School of Alexandria, testified he once delivered a cash payment to Cowhig in the commonwealth's attorney's City Hall office. Other payments, always in cash and "wrapped in a rubber band," were made in front of Alexandria police headquarters, on a street corner near Cowhig's home and "many times" at the bingo parlor.Salahi directed or at the Montessori school, Salahi said.

"I can close you down any time I want, for any reason I want, I am the chief law enforcement officer in the city," Salahi testified Cowhig told him in December 1976.

Cowhig alternated such "harassment" with pats on the knee, telling him "Salahi, I want to be your friend," Salahi told the court during the bribery trial's second day in Alexandria Circuit Court.

Defense attorney Louis Koutoulakos ridiculed the notion that Salaki had bribed Cowhig, telling the jury that Salahi had "concocted" a "beautiful theory" in order to shift police attention away from himself and onto Cowhig, whome he "disliked."

If convicted of bribery, Cowhig could be sentenced to as much as 10 years in prison.

Salahi, who has been granted immunity from prosecution in exchange for his testimony, said that when Cowhig missed receiving payments, he would hold up one, two, three, or four fingers on his next visit to indicate the number of $500 payments he wanted to receive.

The reported earnings of all licensed bingo games in Alexandria last year was $1.2 million, of which more than a third was taken in by Salahi's school. Salahi yesterday called the games a fund-raising "miracle, a life-saver" for the school he had started in 1970.

Salahi, testified that Cowhig began "harassing" him in mid-1976. Cowhig once came to the bingo hall, located at 350 S. Pickett St. in Alexandria, with "five policemen" to close down "instant bingo," a controversial game of chance often likened to slot machine gambling, which all other bingo games in the area were allowed to use, Salahi testified.

Shortly afterward, in May 1976, Virginia State Police investigator Coy Ivy came to the Montessori school of fire at Cowhig's request and said he wanted to examine Salahi's bingo records for a "possible criminal investigation," Salahi said.

In November and December 1976, Salahi said, Cowhig himself told Salahi that his games were illegal, that Salahi was "building an empire. I said, 'My God, what empire? The school gets everything.'" Then Cowhig patted him on the knee and said, "Salahi, I want to be your friend," he testified.

In order to gain "peace" from what he called the cycle of "harassment and compliment," Salahi testified that in early January 1977 "I approached Mr. Cowhig. I said I sponsored bingo games for nonprofit organizations to give them money they needed . . . 'Do you have an organization you would like to sponsor," He said, yes - he was really beaming - 'we can really teach those young children how to fly," by forming an aviation club, Salahi testified.

"I said, 'Great, you form a nonprofit corporation.'"

Salahi said Cowhig later came to him with a two-paragraph form to sign relating to the Ascension Aviation Club and said, "We will need $30,000 to buy a plane" for teaching purposes Salahi said he told Cowhig the group sponsor bingo games on Thursday nights to raise enough money for the down Payment.

Salahi said the form he signed was never returned to him-a point defense lawyer Koutoulakos ripped into on cross-examination, asking Salahi if this was "another lie" designed to get Cowhig, Salahi emotionally denied the charge.

Salahi said he began the series of weekly cash payments to Cowhig, believing he was aiding the aviation club as well as buying peace.

Salahi testified that the first payment he made to Cowhig was $400, instead of $500, though he could not give a reason for the lower figure. The following week when Cowhig came in for the money, according to Salahi, Cowhig said, "Give me another $100, since last week was only $400, let's make it even," so, Salahi said, he gave him $600.

The $500 figure was the standard payment made to groups that sponsored bingo games at the Montessori auditorium, Salahi testified. He said there were no witnesses to any of the transactions.

A private ledger sheet that Salahi began keeping were as well as a tape recording of a conversation between Salahi and Cowhig regarding payments were destroyed when local police investigators began looking into the bingo games in 1978, he testified.

In March 1977 Cowhig called Salahi and said, "We are running out of Los Vegas tickets," a reference to form of instant bingo Cowhig had previously criticized, Salahi testified. The next month, he said, "Cowhig told me, "I am opening my own bingo.Don't worry, I will be behind the scenes and have somebody else take over.'"

Salahi testified that in June 1977 he asked Cowhig, "What's happening to the money?" and the flying club, and Cowhig produced a cashier's check for $12,000 payable to "someplace in Woodbridge," Va. for the purchase of a plane. But last April or May, Salahi said. Cowhig told him "I sold it," meaning the airplane, weeks before the flying club was to begin classes.

Salahi said he was "so happy" when he saw the check, but when Cowhig later said he had sold the plane, "I didn't like it, because all the money was supposed to be going for children. I asked Mr. Cowhig many, many times for the (incorporation) papers for the Ascension Aviation Club, but he ignored me, brushed me aside," Salahi testified.

Salahi said he took the money for Cowhig "off the top" of the games' gross receipts without telling anyone.

When Alexandria lawyer Edward J. White was appointed a special prosecutor last April to look into growing allegations of bingo improprieties, Salahi said he was told by Cowhig, "Don't worry, he's my man."

"How could I go to the police when I thought that you (White) were his man . . . that he controlled the city?" Salahi testified.

Defense lawyers challenged Salahi's quote from Cowhig, producing a copy of a letter Salahi had written in which he referred to a lobbyist for the Montessori school as "my man." "That is your phrase, isn't it?" Koutoulakos asked, but Salahi stuck by his statement.

Salahi said he eventually consulted an attorney, and decided to stop the payments. Cowhig later told him to change his records, that "everyone around here changes records," and told him "not to worry, you worry too much," Salahi testified.

Cowhig was indicted the next day, Aug. 3.

Defense attorney Koutoulakos grilled Salahi on his inability to recall precise dates of alleged payments, and on his admitted lie to police in a July 7 report that he had never made payments to Cowhig.

"You were skimming, weren't you?" Koutoulakos said. Salahi loudly answered, "I was only skimming for Mr. Cowhig." CAPTION: Picture, DIRGHAM SALAHI . . . cities "harassment" by Cowhig