When dissident leader Yuri Orlov was convicted of anti-Soviet slander at his political trial a year ago, a key prosecution charge was that he had coauthored a criminally slanderous report about how the Jews in a rural hamlet called Ilyinka were illegally barred by officials from emigrating to Israel.

The judge said she had seen a movie that showed Ilyinka's inhabitants to be satisfied and happy and the collective farm manager testified the same.

In February, however, two young Jewish activists surfaced here to say they recently journeyed to the remote farming community 400 miles southeast of here, interviewed the families and found Orlov's report to be accurate.

The activists, Evgeny Tzyrlin, 30, and Boris Chernobilsky, 34 said the families live like virtual slaves on the farm, barred by officials from leaving their lawful appeals ingonred, facing threats from police and farm officials. They says that the plight of the five families of would-be immigrants has intimadated others among the 130 Jewish families to Ilyinka from seeking emmigration for themselves.

The farm manager's refusal is based on the fear that if the five families are allowed to leave, a rush by others to follow will leave the collective (kolkhoz) so underpopulated it will be unable to meet harvest quotas, according to the two men.

Early this year, they assert, they were on hand when the farm leadership railroaded yet another decision against the five families. They say the group seeking to emigrate, numbering 42 persons in all, has received letters from relatives in Israel telling of a better life there.

Since they first were refused two years ago, Tzyrlin and Chernobilsky say, the families have refused to work on the kolhoz and have virtually no income.

The men said the group subsists on the livestock they are allowed by the state to own and vegetables reserved from their private gardens. But the managers have denied them the means to haul firewood to their homes for heating and cooking, and on the prairie-like steppe of the black earth zone, where trees are protected by law from being felled, the families are forced to use the lumber and timbers from the sheds and outbuildings around their houses for firewood.

Virtually all of Ilyinka's 1,000 inhabitants are Jewish, the two men say. Jews here believe the hamlet is perhaps the only such all-Jewish farm community left in European Russia. Others were annihilated during World War II.

A dozen families left Ilyinka for Israel in 1974-6, but no other emigration has since been allowed, they said. The Jewish families average about six children per couple, far higher than the size of Russian families on the kolkhoz, and thus constitute much of its raw labor.

Formerly a separate collective farm known as "Jewish Peasant" before the war, Ilyinka, according to the two men, was merged after the war with three other Russian-dominated hamlets into a larger collective renamed "Russia."

One of the two activists said he managed to attend an annual meeting Feb. 3 of the collective farmers at which farm director A. G. Kuvaldin summarily dismissed the families' petition to leave by railroading a false vote against them.

The Moscow activists say they were harassed and interrogated by police when they arrived in Ilyinka, which is so isolated that strangers are immediately reported to the police by bus drivers and other state workers.

Jews here say the situation in Ilyinka is just one more example of how the Soviet Union continues to prevent Jews from emigrating to join relatives in Israel, despite Kremlin pledges on issues of international human rights.

More than 31,000 Soviet Jews were allowed to emigrate in 1978, the highest number since 1973. There are an estimated 2.5 million to 3 million Jews the Soviet Union's population of 261 million. CAPTION: Map, No caption, By Dave Cook - The Washington Post