The Baltimore Orioles probably will treat 1980 as an "attendance test year" and not play any home games outside Memorial Stadium until 1981, if then, the team's general manager indicated today.

Any plans to move games, or eventually the franchise, to Washington, now that Washingtonian Edward Bennett Williams has bought the team, are on a back burner.

"My sense, after talking with Williams for the first time this week, is that we would not play any games in Washington next season," Hank Peters said today.

"I assume we'll give Baltimore one complete year to show what's it's going to do. We have to find out if our attendance this year is a fluke or if we suddenly have a new attendance pattern after 25 years.

"We have a year to relax and see what happens. There's no pressure and no hurry. Why would we want to do anything to tamper with the enthusiasm that we have now in Baltimore?"

Peters emphasized he was not speaking for Williams and that no decision had been announced for next season. But, he added, "I would think Williams would say something when he's definitely made up his mind . . . probably in a week or so."

Williams could not be reached for comment.

The first common sense assumption of many fans, when sale of the club to Williams was announced two weeks ago, was that the Birds definitely were headed for Washington -- either sooner or later. However, since the O's already have set a franchise attendance record of 1,226,484, with 17 home dates still to play, the "sooner" half of that idea appears dead.

"Williams has bought two gold mines at one time," an Oriole official said today. "He's not going to stop mining the ore out of the mine in Baltimore when it's going strong. He's always got the other mine in Washington to fall back on."

The Orioles' feelings toward Washington have changed dramatically since an attendance eruption here early this season.

"I think the general feeling in Baltimore until just a few weeks ago was that the only salvation for the franchise was to split the schedule in some way with Washington," said Peters. "People here just figured it was inevitable."

A unique set of circumstances give the Orioles what Peters calls "a year to relax and evaluate."

The trauma of the Hoffberger family selling the franchise, and acting like a flirt for two years in the process, is past. Also, students of baseball statistics know that when a city has a sudden burst of baseball fever at the gate, the attendance graph reaches its peak the year after that club makes it to the World Series or becomes world champion.

"Historically, you'd have to say that our attendance here is more likely to get better before it gets worse," said Peters.

The Orioles also have reached a relative lull in the free-agent miseries that have racked the club since 1976. Most of the team's key young players -- Eddie Murray, Mike Flanagan, Dennis Martinez -- are tied to the club for three more years.

"A lot of decisions will have to be made with the new owner," said Peters. "I know he isn't interested in a think except keeping this club a winner and going first class. Mediocrity doesn't interest him.

"Will he want to go wild in the free-agent market? I doubt it, but I don't know. What we do know is that we have three more years before we have to make major choices about Eddie and Mike and Dennis and several other players.

"We don't have to rush and we aren't pressed immediately by multimillion-dollar contracts hanging over our heads."

For this season, the attendance goal is 1.6 million, "which would be about the league average," said Peters. "Of course, the attendance we reach this year and next would presumably represent an absolute maximum for Baltimore since I don't know how we could put a much better product on the field.

Despite the O's much improved ticket count, Peters did not deny that this city still was under the gun at the turnstile -- especially in the face of free-agent expenses and baseball's rising popularity each year, which makes an attendance figure of 1.6 million seem ordinary compared with the majority of cities.

"All your standards have to change with the years" said Peters. "Everybody's attendance is rising, in general. We assume that player salaries aren't going to go down much in the future. The questions, 'How much do we need to operate successfully? What is our bottom line?' are still up in the air as far as our new owner is concerned."

Williams and the Orioles are still in the first stages of getting acquainted.While Williams has been successful in sports as president of the Washington Redskins, the Orioles have been even more exemplary -- winning more games than any team in baseball for the last 12 years.

"I asked Williams if the Redskin offices were in RFK Stadium," Peters said, grinning. "He said, 'Oh, no. We have our own complex out by Dulles Airport.'"