Jewish activist Viktor Brailovsky was sentenced to five years' internal exile today after being found guilty of anti-Soviet defamation by a Moscow city court at the end of a two-day trial.

The sentence was less severe than expected by many in the Jewish community.

The maximum punishment is three years' labor camp imprisonment, which Brailovsky's wife, Irina, said after the trial would have "been a death sentence" because of her husband's poor health. Many U.S. and West European scientists had appealed to the Soviets on behalf of the 45-year-odl cyberneticist.

Brailovsky had helped organize scientific seminars in his house for Jews who, like him, have been refused permission to emigrate, and he was editor of a samizdat journal, Jews in the U.S.S.R. He was arrested in November.

Because Soviet regulations count every day of imprisonment as three days of exile, he effectively will be banished from Moscow for about three years.

The place of banishment, likely in Siberia, will be decided by the Interior Ministry after he has appealed his case, which could take about two months. Internal banishment, a traditional Russian punishment for political activism, has been used in recent years against other Jewish activisits.

Those banished may be joined by their families but are under tight police restrictions on their movements.

About 30 supporters and friends, as well as correspondents and U.S., British and Australian diplomats, barred from attending, stood outside the courthouse.

The state had charged that Jews in the U.S.S.R. defamed the Soviet system in part by alleging that it pursued anti-Semitic policies. In a summary defense sppech that lasted about an hour, according to his wife, Brailovsky said the fact that he and his family have been denied exit permission for more than eight years demonstrted discrimination.