Bob Trout's Roosevelt days

''The man who invented the 'Fireside Chat' '' temporarily left his post as ABC bureau chief in Madrid to visit New York and talk about the good old days of radio.

Not Franklin Delano Roosevelt, but radio announcer Robert Trout.

''And I didn't really invent the phrase 'Fireside Chat,' although everybody seems to give me credit for it -- I was just the first person to use it on the air. It was my boss at the time who actually wrote the words,'' he explains, seated in his borrowed ABC News office.

Trout, who spent most of his career as a radio newsman with CBS, is in New York to act as narrator of an ABC News three-hour TV special, ''FDR'' (Friday, Jan. 29, 8-11 p.m.), which celebrates FDR's 100th birthday Saturday. All week long, television stations have been airing specials to commemorate the date.

Most people who lived through the Great Depression remember Bob Trout vividly as the radio announcer who almost always introduced the President. He is known as the dean of radio announcers. When called that to his face, this tall, slim man with a wry sense of humor almost blushes.

''I guess they can't think of anybody who has been around longer,'' he says. ''I started just about 50 years ago.''

Trout was captivated by Roosevelt from the very beginning. ''The man had total charisma,'' he says. ''Everybody used to say that this man with the golden voice would lead America into dictatorship, using his almost perfect voice to lure the people. But the threat was no more real than it is now with Reagan's professional skills. I hear the same things about the danger of TV these days.''

Trout's most vivid memory of the Roosevelt era was traveling on the President's campaign train. ''It ruined me for any other kind of travel. I'll never forget raising the shade in my sleeper just a crack to see the dawn and there were people at the side of the tracks, silently waving, even though FDR was fast asleep. They'd come a long way to wave.''

Trout wonders if the press today would be able to maintain the silence that radio managed in regard to FDR's physical disability. ''Then it was only on radio, and the only photos you usually saw of him were shots of him sitting. He had a magnificently strong upper torso, so it was hard to realize that he wore braces. Nobody ever mentioned his wheelchair. Today, aside from the visibility of TV, ethics and manners have changed.

''I remember once, there was some mistake in the arrangements and he had to walk a long distance to the podium. Halfway there he turned around to those who had wheeled him in and shouted: ''Don't worry, I'll make it.' ''

According to Trout, Roosevelt had a devilish sense of humor. ''I'll never forget the day in 1936 when he came to Philadelphia to accept his second-term nomination. I was at the railroad tracks, filling in live while we waited for the train to stop. Finally, the train stopped and, with great relief, I said, 'Well, the train is here at last and the President will be emerging in a moment.'' He didn't come out. We waited for a long time, with me having to talk all the while. I was frantic.

''Several years later I learned that he told some newspapermen that he had been listening to me on the radio and was all set to step out of the train when the thought hit him: 'What will he say if I don't come out. . . .' Then, he sat down and waited.''

Trout laughs at the joke on himself. ''FDR was a great speaker on the air, but he was also a great talker. I remember a big reception for newsmen at the White House. A line formed as we wended our way up the stairway and greeted Mrs. Roosevelt at the door. We advanced very slowly, because across the room there was Franklin D. Roosevelt, chatting with everybody who passed by.

'' 'Father, you simply must stop holding up the line,' Mrs. Roosevelt shouted. She called him 'Father' all the time.''

Trout has served as radio or TV newsman through many presidents -- FDR, Truman, Eisenhower, Kennedy, Johnson, Nixon, Ford, Carter, Reagan -- how would he rank their charisma?

"I have to say that Roosevelt is No. 1, without doubt. But I think that Kennedy and Reagan would tie for second place. Each is quite good in his own way.''

Trout doesn't believe, even if there weren't a constitutional amendment against it, that any president could ever again win four terms.

''People get disillusioned very quickly these days,'' he says, ''and they have shorter attention spans. The voting public is also always promised more than can possibly be delivered, and their manners as well as their patience cause them to want a change. So I'm afraid one term will be all anyone can expect. . . .

''But wasn't that true in FDR's time, too? Didn't candidates overpromise?''

No. FDR never had a program. He just tried one thing after another while, as he himself said, he kept his finger in the dike. He'd be horrified if he heard people worship 'the New Deal.' He felt that every presidential term required special handling. Many times I heard him say that nothing in politics is for eternity.

''If Bob Trout, newsman, had to use one adjective to describe the FDR he knew , what would that be?

He thinks for a moment. ''Alive!'' But then he shakes his head. ''One word can't do it. As a thorough newsman I would have to also add dynamic, vigorous, cheerful, optimistic, perhaps the most inspiring example in history of somebody who overcame seemingly unsurmountable odds. . . .

''The adjectives were still flowing when we bade adieu to the dean.