Fran Tarkenton, who did all the talking in his professional football huddles for 18 seasons, retired at 39 yesterday and will perform in ABC's chatter box with Howard Cosell and Frank Gifford on Monday night telecasts.

The Minnesota Viking Quarterback, in effect, will be a replacement for Don Meredith in six games. Under a multiyear contract, he also will work three exhibitions and the Pro Bowl.

In addition, WXIA-TV in Atlanta announced last night that Tarkenton had signed a separate contract to do two weekly sports features and a fall football predictions program for the ABC affiliate.

Appearing on WXIA's evening newscast , Tarkenton said he was leaving professional football "happy, with great memories."

Asked if he felt his football career was unfulfilled because the Vikings never won a Super Bowl, he said, "If we'd won one it would still be unfulfilled, because you never do all that you want to do."

Tarkenton said the big change in pro football during his career was in the way quarterbacks play the game.

"When I came up, quarterbacks didn't run at all," he said. "I was a freak - a scrambling quarterbacks, a running quarterback. A person who threw out of the roll-out, out of the play action.

"Now, rather than being the exception, it is the rule.

"Most of the quarterbacks in our league today are mobile and run," he said. "Things change. I took my raps. I was the first of the change."

Tarkenton said he was looking forward to a career in television and believed the transition will be easy.

Tarkenton holds every major Notional Football League passing record, but had the misfortune to quarterback three of the Vikings' four losing Super Bowl teams.

He was a commentator the last three years on NBC pregame telecasts. He was the first player interviewed by Cosell when ABC began the Monday night telecasts with an exhibition game between the Pittsburgh Steelers and the NEW YORK Giants on Aug. 28, 1970.

Viking staff member said Tarkenton might have made his decision to retire when he was booed at a home game by fans who also called for Tommy Kramer to replace him.

"Francis is the greatest quarterback ever to play the game," said Coach Bud Grant. "The fact that he can go out on top at age 39 is a testimonial to his great ability. A lot of players retire from the game going kownhill.

"He could have played another year. He can still move, can run, and has good enthusiasm. His mind is sharp and physically he doesn't have any problems."

A spokesman for the Vikings said Tarkenton "had one thing to prove last season - that he could come back from a broken leg suffered in the ninth game in 1977, because otherwise it would have been a sudden and inglorious end to a career, being carried off the field. He thought he played as well as ever in 1978.

"He had a lot of strain because he almost carried the club after Chuck Foreman suffered a knee injury."

Grant had said after Tarkenton told the Vikings he might go into television, "If Francis decides not to come back we're pretty well fixed at quarterback."

Kramer is coming up to his third season and Bob Lee his 11th. The Vikings picked Steve Dils of Stanford on the fourth round of the draft last week.

Kramer did not play again after suffering a concussion against Los Angeles in the Vikings' seventh game last season. He did not even practice for two weeks after being tackled by line-backer Jim Youngblood.

The expansion Vikings drafted Tarkenton out of Georgia on the third round in 1961. In the first regular-season game that year, he came off the bench and upset the Chicago Bears, 37-13, with four touchdown passes.

But by the end of the 1966 season he had fallen into disfavor with Coach Norm Van Brocklin and was traded to the New York Giants.

Because the Vikings had a 7-7 record with Tarkenton in 1965 and the Giants 7-7 seasons with him at quarterback in 1967 and '68, Viking General Manager Jim Finks was quoted as saying "Here Lies Fran Tarkenton 7-7."

Yet the Vikings traded to get him back from the Giants in 1972 and he led them into Super Bowls in 1974, 1975 and 1977.

Tarkenton once asked Roger Staubach of the Dallas Cowboys, as an interviewer for NBC during Super Bowl Week, "Don't you object to (Coach) Tom Landry calling the plays for you?"

"Not at all," Staubach replied. "Maybe if Bud Grant called them for you, you would be in the Super Bowl."