In Pittsburgh, doubts about Reagan's message

As a chunky union laborer took his place in the unemployment line for the first time here Wednesday morning, he said he found it ''hard to believe America is on the mend.''

He was laid off the same night Ronald Reagan gave his State of the Union message suggesting that things are on the mend.

From this pocket of severe unemployment, the perspective on the state of the Union is different from that spelled out by President Reagan. Even with his offerings of extended unemployment benefits, incentives for employers to hire long-term unemployed, and retraining and youth employment programs, the President's message was met largely with cynicism here among both the employed and unemployed.

This state is heavily dependent on the steel industry, which has seen production cutbacks of more than 50 percent in the past year. Unemployment runs at a rate of 12.7 percent, according to John Lester Jr., manager of the state employment service office. His office sees 12,000 to 13,000 unemployed a week. But he adds that in some pockets, unemployment is as high as 30 percent.

On most days, the lines of unemployed can flow out onto the street at the Metro South Pennsylvania state employment service office. Some people here need no prompting; they are already discussing Mr. Reagan's speech. And while admitting they helped put him in office, they think he is unaware of their plight.

Others dismiss the topic, adding that they've reached a point wherethey believe neither Reagan nor any other politician can turn the economic tide. Still others, admittedly a minority, say they think the President's programs will ultimately please them.

''Specifics - there weren't any in his speech,'' says Rob Toy, spokesman for the Mon Valley Unemployed Committee, which received attention earlier this month for getting the Allegheny County sheriff to take 42 homes off a foreclosure sale.

Mr. Toy, unemployed for a year, says the 1,100-member committee largely views the proposals as promises without any bite. Retraining, for example, could cost millions of dollars, and that doesn't fit with the President's proposed spending freeze.

Officials at the United Steelworkers of America also complain about vagueness. Pete Eritano, president of a local in Aliquippa, Pa., where 7,500 of 10,000 members have been idled, says ''the general opinion around here, whether it is steelworkers, truckdrivers, or small-business men, is that they've lost hope in Ronald Reagan.''

He says extension of unemployment benefits would be welcome. But, he adds, offering incentives to employers to hire the jobless ''won't make a difference because there aren't any jobs out there if there is no pipe to be made or steel to be made.''

Even some who still have jobs are wary of Reagan. One waitress at a downtown hotel clings by a thread to her job. Management cut everyone's hours to 24 a week so that all could keep their jobs.

''If I wasn't a waitress, I probably wouldn't be working at all,'' she says, adding many people she knows in the steel and manufacturing industries were laid off long ago. Echoing others, she explains, ''Reagan's a nice man, but he doesn't know what he's doing to workers. He's not working-class.''

Joe Stephon, an elevator constructor, has been jobless for four months. But, he says, ''I'd vote for Reagan again. He's facing up to the problems others [ presidents] caused.''