President Reagan took his moment of triumph quietly, making it clear that he believes his victory on AWACS will make him a stronger foreign-policy maker, thanking the Senate for its vote, but not crowing about the powers of persuasion he unleashed once again to win an uphill legislative fight.

Minutes after the 52-to-48 Senate vote, Reagan sat at his Oval Office desk and read a brief prepared statement. Selling the Airborne Warning and Control System not only improves U.S.-Saudi relations, but helps protect the U.S. "economic lifeline" to Saudi oil and ultimately contributes to the progress toward peace in the Middle East, he said.

"Today, I think, we have seen the upper chamber at its best," he said, praising Senate Majority Leader Howard H. Baker Jr. (R-Tenn.) and those who helped him.

For Reagan, yesterday was almost like an election day at the end of a long campaign. There was little left for him to do. In a final bid for votes, the president saw Sens. Edward Zorinsky (D-Neb.) and David Pryor (D-Ark.), but his schedule was kept largely blank to make him available if personal intervention was needed to stem a sudden hemorrhage, aides said. It wasn't, so Reagan spent the balance of the day in the White House living quarters with his wife and in the second-floor study off his bedroom that he used so effectively in his last blitz of one-on-one lobbying with senators.

Just before the senators began voting, Reagan went to the Oval Office to await the result.

Down the hall in the West Wing, White House chief of staff James A. Baker III, Secretary of State Alexander M. Haig Jr. and the president's national security adviser, Richard V. Allen, listened over a telephone squawk-box hookup to the clerk of the Senate calling the roll.

Baker sat at the head of the table keeping tally with a red pen, with Haig and Allen flanking him. Deputy chief of staff Michael K. Deaver stood looking over Baker's shoulder. No one spoke as dozens of television and still cameras recorded the carefully arranged scene.

Zorinsky, the last senator called by the clerk--and one of the two given the president's personal lobbying appeal yesterday, provided the icing on the cake. When the Nebraska Democrat voted with the president, Baker allowed himself his only exclamation of pleasure and his aide, Richard Darman, exclaimed: "That's it!"

Baker led the way to the Oval Office to tell Reagan he had won 52 votes, two more than he needed. A reporter suggested that since Baker was now out of view of the cameras he could exult a little. "Yes, now I can say 'whoopee,' " he agreed quietly.

"Thank God," the president said when he got the result, according to deputy press secretary Larry Speakes. Reagan told reporters later he had known since early afternoon that he had 50 votes, enough for him to win.

He was asked whether his victory would help him in dealing with foreign leaders.

"I think it's going to have a very good effect. We had heard from many leaders who had expressed their concern for what this would mean on the whole world scene," Reagan replied.

For six weeks the White House put on an intense lobbying campaign to win on AWACS. When the president returned from his August California vacation he had allowed his opposition lots of time to organize, and more than 50 senators appeared committed against the sale.

White House spokesmen welcomed their role as the underdog, but they knew that the winning numbers were within reach if they made the right appeals to various senators. There are 53 Republican senators and Reagan is enormously strong within his party. He could argue the merits of the case, but he could also make it a test of support of a president who had given his word to a foreign nation.

"Contrary to what has been said, there have been no deals made. None were offered," Reagan told reporters after the vote.

The lobbying was intense, as Pryor noted when he compared the pressure to that of his state's former governor, Orville Faubus, who he said would twist both arms and both legs.

Speakes put it more delicately, saying the vote "is one more item of proof that the president does have a very good legislative technique."