NEW YORK (AP) _ Mikhail S. Gorbachev's image flickered on the black-and-white television screen, a translator's voice muffling the Soviet president's strenuous defense of new Soviet laws on Jewish emigration.

''He's just repeating the same things we've heard already,'' muttered Manashir Ifraimov, one of thousands of Soviet immigrants settled in the Brighton Beach section of Brooklyn.

Like other emigres in this vibrant community dubbed ''Little Odessa,'' he paid casual but constant attention to the events across the East River on Wednesday, as Gorbachev spoke to the United Nations and toured Manhattan during a visit shortened by an earthquake in the southern Soviet Union.

''We've heard these words. Now he has to make them real,'' Ifraimov said.

Ifraimov, an economist-turned-butcher who emigrated two months ago from Soviet Azerbaijan, turned from the TV to finish slicing a customer's ham.

''People are accustomed to a lot of talking, but people don't always believe it,'' Ifraimov said. ''They are used to living with promises. They just want their kids to have a better life.''

New York's Soviet immigrants differed in their degree of optimism about the visiting leader's reforms. But many lauded glasnost - Gorbachev's policy of openness - for enabling them and their families to leave or travel from the Soviet Union more freely than ever imagined.

''I would not leave if I was there now,'' said Rimma Melik, owner of the popular Kavkas Restaurant, who emigrated here in 1978 and has visited her family in the Soviet Union twice in recent years.

Gorbachev's glasnost and perestroika, his program of economic and social restructuring, have played well even among stalwart critics who insist the reforms are little more than a publicity stunt.

''People are not getting better. Housing and roads are falling apart,'' said Sophia Perett, executive director of the Center For Russian Immigrants. ''People's main concern is to have food on the table and to get by every month. For them nothing has changed.''

Still, there has been a very real increase in tourist and exit visas, she said. The last large wave of emigration ended in 1979 with detente.

Last year some 1,500 immigrants received tourist visas through the People's Travel Club, said Leon Kogan, manager of the agency's Brighton Beach branch. Other travel agents reported similar increases, a sign of the times under Gorbachev's glasnost.

''We expect the number to be higher this year,'' he said.

Groups of rabbis, artists, writers, students and performers are streaming in and out of the Soviet Union, singing the praises of ''Gorbachevism, '' as one new emigre book labels it.

Mrs. Melik agreed that living conditions in the Soviet Union have not changed. But she said Gorbachev has reignited hope for the future, a feeling she said means the difference between staying or leaving.

She said Soviet scientists and professionals, the kind Gorbachev needs to reshape his country, will decide to stay when conditions improve.

''Most important is that people love their Motherland. People who had to wait 10 to 20 years are now more free to show their work. And they will make this country, if they will be allowed. It will be a great county,'' she said.

Emigrants give Gorbachev credit more for what could happen than what has happened, realizing much also depends on relations with the United States.

''I support any contact, even negative contact,'' said Ifraimov, whose brother arrived in New York last week after waiting just two months for an exit visa.

When asked what he would say if Gorbachev was standing right in front of his butcher counter, Ifraimov didn't hesitate a moment.

''I'd say, 'You're on the right course.' ''