In the business that I used to be in" the old actor was saying as his chartered jet circled to land "you learn not to stay on stage too long." You learn there's a time you have to exit.

"I think you can read it. The audiences tells you" he added. "The old stage rule is that you always leave them wanting more."

So after all these seasons Reagan at 67, is still on the political state. Both the actor and the politician in him tell him this is no time for final bows.

And probably no other out-of-office politician in history has been able to muster the resources that Reagan and his associates control.

He has scheduled 80 campaigns stops in 26 states this tall. He is writing letters and making commercials for Republican candidates - 54 radio endorsements and 12 television tapes last week. And the Citizens for the Republic the political action committee his former associates control plans to fannel $500,000 into various congressional campaigns by late October.

Everywhere he goes, the crowds pack the halls - 950at a $50-a-head fund-raiser at noon here Friday, for example. They stand in lines 50 deep to get his autograph. The old women and the young girls grasp at his hand and say things like. "I pray for the day you become president."

The former California governor, who was edged out of the 1976 Republican presidential nomination by President Ford leaves little doubt that he will run again in 1980.

"I've not closed the door on that," he told a news conference in Chicago Friday morning repeating almost the exact words here three hours later. "There's a distinct possibility that I'll be a candidate."

The big question he bumps into wherever he goes is his age. Reagan will be 69 in 1980 a year older than William Henry Harrison the country's oldest president who died a month after his inauguration in 1841.

Reagan has a stock answer for that. "The only place I ever get that question is at press conferences" he says. "You know I was in the Orient last April. They thought I was too young."

Timing of course is the essence of theater and politics. And this is not the time to say more or less about 1980.

This is a time for staying visible as a party spokesman and building up political IOUs. Reagan is doing that campaigning for Republicans around the country just as Richard Nixon did in the years before his comeback in 1968.

"There's no question that this business of politics is a backscratching business," says Lyn NOfziger executive director of the Citizens for the Republic and a longtime Reagan adviser.

Few groups in the country can provide as much backscratching as CFTR which was formed after the 1976 presidential campaign with $15 million in campaign funds that came in after the Republican National Convention. Reagan is chairman of the group.

According to its latest report with the Federal Election Commission the group had given eight Republican senatorial candidates and 84 House candidates a total of $137,924 by Sept. 19 about a third of the amount it intends to spend this fall. It also pays all of Reagan's traveling expenses conducts seminars publishers a newsletter and maintains 18 people on the full-time payroll.

Reagan and CFTR concentrate their efforts on three types of candidates: former Reagan supporters to whom they owe a moral debt: mainstream Republicans with a good chance of winning this fall and attractive young conservatives who show long-term political potential even if they don't win this fall.

"We don't care if everyone supported us in '76 but we say they should be basically conservative and that they accept the Republicans platform adopted in Kansas City." Nofziger says. "We're obviously not going to ask him [Reagan] to campaign for a very liberal Republican or people we know have very little chance of winning."

In the case of Reagan's campaign trip to Evansville a city of about 140,000 on the Ohio River in southeastern Indiana the candidate was Joel Deckard a conservative Republican given a better-than-even chance of beating one-term Democratic incumbent Rep. David L. Cornwell.

Deckard had expected Reagan to draw a crowd of no more than 800. Somewhere between 950 and 1,000 people showed up, each paying $50 apiece.

Reagan's speech was one of a half dozen he has written out in longhand on white file cards he keeps in his briefcase. His delivery ws smooth as silk; his message about the evils of big government was the same he has been delighting groups of businessmen and the party faithful with for years.

It began with a litany of Jimmy Carter jokes. "President Carter is saying he has trouble communicating with Democrats in Congress," he said. "Maybe he should learn to speak Korean."

"They say Bill Carter earns five times as much as his brother. That's foolish. He's only worth twice as much." he said later. "We have a president who doesn't allow alcoholic beverages to be served in the White House but whose aides smoke pot. That makes this the first administration in history that can be truly called high and dry."

The crowd loved it. And just as the laughter died down, he added, "Any man who tells you he enjoys a cold shower will lie about other things."

Then he launched into the heart of his speech, a wholesale attack on the Democrats, how their wasteful spending has nearly bankrupted the country, how they've allowed the United States to sink to a second-rate power, how Proposition 13 in California scared them half to death.

Democrats are now dancing "the Waffler's Waltz," he said. "They are engaged in the most deceitful and massive rewriting of history ever attempted in American politics by telling the American people that high taxes, inflation, budget-busting and other forms of economic lunacy just happened and weren't caused by Democratic policies."

The Republican Party has a golden opportunity to capitalize on the national unrest over inflation and high taxes he said: "Only rarely is a political party fortunate enough to be able to say: 'This historic moment is ours to grasp. What we have always believed, the people now demand.'"

When he finished, the crowd surged toward him. Regan shook hands and signed autographs for 15 minutes then left. About 25 people were still waiting in line.

The audience still wanted more. And 1978 is no time for Ronald Reagan, the politician and old actor, to leave the stage.